231545220 has 48 divisors (see below), whose sum is σ = 649360320. Its totient is φ = 61646976.

The previous prime is 231545201. The next prime is 231545243. The reversal of 231545220 is 22545132.

It is a super-2 number, since 2×231545220² = 107226377809696800, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 39819 + ... + 45261.

It is an arithmetic number, because the mean of its divisors is an integer number (13528340).

Almost surely, 2^231545220 is an apocalyptic number.

231545220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

231545220 is an abundant number, since it is smaller than the sum of its proper divisors (417815100).

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

231545220 is a wasteful number, since it uses less digits than its factorization.

231545220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6164 (or 6162 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 24.

The square root of 231545220 is about 15216.6100035455. The cubic root of 231545220 is about 614.0616001321.

The spelling of 231545220 in words is "two hundred thirty-one million, five hundred forty-five thousand, two hundred twenty".