215131163400 has 72 divisors (see below), whose sum is σ = 722482163130. Its totient is φ = 57368309760.

The previous prime is 215131163369. The next prime is 215131163411. The reversal of 215131163400 is 4361131512.

It is a happy number.

215131163400 is a `hidden beast` number, since 2 + 1 + 5 + 1 + 311 + 6 + 340 + 0 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 187813023876 + 27318139524 = 433374^2 + 165282^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 59756857 + ... + 59760456.

Almost surely, 2^215131163400 is an apocalyptic number.

215131163400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

215131163400 is an abundant number, since it is smaller than the sum of its proper divisors (507350999730).

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

215131163400 is a wasteful number, since it uses less digits than its factorization.

215131163400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 119517335 (or 119517323 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

Adding to 215131163400 its reverse (4361131512), we get a palindrome (219492294912).

The spelling of 215131163400 in words is "two hundred fifteen billion, one hundred thirty-one million, one hundred sixty-three thousand, four hundred".