216322631 has 4 divisors (see below), whose sum is σ = 247225872. Its totient is φ = 185419392.

The previous prime is 216322597. The next prime is 216322669. The reversal of 216322631 is 136223612.

216322631 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 216322631 - 2¹⁴ = 216306247 is a prime.

It is a super-2 number, since 2×216322631² = 93590961365524322, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 216322631.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216322231) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15451610 + ... + 15451623.

It is an arithmetic number, because the mean of its divisors is an integer number (61806468).

Almost surely, 2^216322631 is an apocalyptic number.

216322631 is a deficient number, since it is larger than the sum of its proper divisors (30903241).

216322631 is an equidigital number, since it uses as much as digits as its factorization.

216322631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30903240.

The product of its digits is 2592, while the sum is 26.

The square root of 216322631 is about 14707.9104906169. The cubic root of 216322631 is about 600.2985837956.

The spelling of 216322631 in words is "two hundred sixteen million, three hundred twenty-two thousand, six hundred thirty-one".