2161526640 has 320 divisors, whose sum is σ = 8682777600. Its totient is φ = 431972352.

The previous prime is 2161526639. The next prime is 2161526641. The reversal of 2161526640 is 466251612.

It is an interprime number because it is at equal distance from previous prime (2161526639) and next prime (2161526641).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2161526641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 412356 + ... + 417564.

It is an arithmetic number, because the mean of its divisors is an integer number (27133680).

Almost surely, 2^2161526640 is an apocalyptic number.

2161526640 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 2161526640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4341388800).

2161526640 is an abundant number, since it is smaller than the sum of its proper divisors (6521250960).

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

2161526640 is a wasteful number, since it uses less digits than its factorization.

2161526640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5264 (or 5258 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 33.

The square root of 2161526640 is about 46492.2212848558. The cubic root of 2161526640 is about 1292.9652836121.

The spelling of 2161526640 in words is "two billion, one hundred sixty-one million, five hundred twenty-six thousand, six hundred forty".