2161515672 has 64 divisors (see below), whose sum is σ = 6197913600. Its totient is φ = 697260960.

The previous prime is 2161515661. The next prime is 2161515679. The reversal of 2161515672 is 2765151612.

2161515672 is a `hidden beast` number, since 21 + 61 + 515 + 67 + 2 = 666.

It is a super-3 number, since 3×2161515672³ (a number of 29 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2161515679) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 154708 + ... + 168099.

It is an arithmetic number, because the mean of its divisors is an integer number (96842400).

Almost surely, 2^2161515672 is an apocalyptic number.

It is an amenable number.

2161515672 is an abundant number, since it is smaller than the sum of its proper divisors (4036397928).

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

2161515672 is a wasteful number, since it uses less digits than its factorization.

2161515672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 322853 (or 322843 counting only the distinct ones).

The product of its digits is 25200, while the sum is 36.

The square root of 2161515672 is about 46492.1033294903. The cubic root of 2161515672 is about 1292.9630966906.

The spelling of 2161515672 in words is "two billion, one hundred sixty-one million, five hundred fifteen thousand, six hundred seventy-two".