216156631 has 8 divisors (see below), whose sum is σ = 220767120. Its totient is φ = 211565952.

The previous prime is 216156623. The next prime is 216156697. The reversal of 216156631 is 136651612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 216156631 - 2³ = 216156623 is a prime.

It is a super-2 number, since 2×216156631² = 93447378250540322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 216156593 and 216156602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216156131) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18240 + ... + 27658.

It is an arithmetic number, because the mean of its divisors is an integer number (27595890).

Almost surely, 2^216156631 is an apocalyptic number.

216156631 is a deficient number, since it is larger than the sum of its proper divisors (4610489).

216156631 is an equidigital number, since it uses as much as digits as its factorization.

216156631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9905.

The product of its digits is 6480, while the sum is 31.

The square root of 216156631 is about 14702.2661858640. The cubic root of 216156631 is about 600.1449936623.

The spelling of 216156631 in words is "two hundred sixteen million, one hundred fifty-six thousand, six hundred thirty-one".