2115900864 has 252 divisors, whose sum is σ = 7620408432. Its totient is φ = 549457920.

The previous prime is 2115900851. The next prime is 2115900883. The reversal of 2115900864 is 4680095112.

2115900864 is a `hidden beast` number, since 2 + 1 + 1 + 590 + 0 + 8 + 64 = 666.

It is a tau number, because it is divible by the number of its divisors (252).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 485704 + ... + 490040.

It is an arithmetic number, because the mean of its divisors is an integer number (30239716).

Almost surely, 2^2115900864 is an apocalyptic number.

2115900864 is a gapful number since it is divisible by the number (24) 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 2115900864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3810204216).

2115900864 is an abundant number, since it is smaller than the sum of its proper divisors (5504507568).

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

2115900864 is a wasteful number, since it uses less digits than its factorization.

2115900864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4384 (or 4360 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 36.

The square root of 2115900864 is about 45998.9224221612. The cubic root of 2115900864 is about 1283.8031549639.

Adding to 2115900864 its reverse (4680095112), we get a palindrome (6795995976).

The spelling of 2115900864 in words is "two billion, one hundred fifteen million, nine hundred thousand, eight hundred sixty-four".