2158611840 has 768 divisors, whose sum is σ = 9654128640. Its totient is φ = 431308800.

The previous prime is 2158611827. The next prime is 2158611841. The reversal of 2158611840 is 481168512.

2158611840 is a `hidden beast` number, since 21 + 586 + 1 + 18 + 40 = 666.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 2158611795 and 2158611804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2158611841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 13749042 + ... + 13749198.

It is an arithmetic number, because the mean of its divisors is an integer number (12570480).

Almost surely, 2^2158611840 is an apocalyptic number.

2158611840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2158611840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4827064320).

2158611840 is an abundant number, since it is smaller than the sum of its proper divisors (7495516800).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2158611840 is a wasteful number, since it uses less digits than its factorization.

2158611840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 231 (or 216 counting only the distinct ones).

The product of its (nonzero) digits is 15360, while the sum is 36.

The square root of 2158611840 is about 46460.8635305027. The cubic root of 2158611840 is about 1292.3838380041.

The spelling of 2158611840 in words is "two billion, one hundred fifty-eight million, six hundred eleven thousand, eight hundred forty".