231564216 has 32 divisors (see below), whose sum is σ = 623442960. Its totient is φ = 71250432.

The previous prime is 231564211. The next prime is 231564227. The reversal of 231564216 is 612465132.

It is a super-2 number, since 2×231564216² = 107243972263389312, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231564211) 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, 370785 + ... + 371408.

Almost surely, 2^231564216 is an apocalyptic number.

231564216 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

231564216 is an abundant number, since it is smaller than the sum of its proper divisors (391878744).

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

231564216 is a wasteful number, since it uses less digits than its factorization.

231564216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 742215 (or 742211 counting only the distinct ones).

The product of its digits is 8640, while the sum is 30.

The square root of 231564216 is about 15217.2341770770. The cubic root of 231564216 is about 614.0783922374.

It can be divided in two parts, 23156 and 4216, that added together give a palindrome (27372).

The spelling of 231564216 in words is "two hundred thirty-one million, five hundred sixty-four thousand, two hundred sixteen".