231366021 has 16 divisors (see below), whose sum is σ = 325731840. Its totient is φ = 145672560.

The previous prime is 231366013. The next prime is 231366029. The reversal of 231366021 is 120663132.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (231366013) and next prime (231366029).

It is not a de Polignac number, because 231366021 - 2³ = 231366013 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 231365982 and 231366000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231366029) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12736 + ... + 24998.

It is an arithmetic number, because the mean of its divisors is an integer number (20358240).

Almost surely, 2^231366021 is an apocalyptic number.

It is an amenable number.

231366021 is a deficient number, since it is larger than the sum of its proper divisors (94365819).

231366021 is a wasteful number, since it uses less digits than its factorization.

231366021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12616.

The product of its (nonzero) digits is 1296, while the sum is 24.

The square root of 231366021 is about 15210.7205943703. The cubic root of 231366021 is about 613.9031463833.

The spelling of 231366021 in words is "two hundred thirty-one million, three hundred sixty-six thousand, twenty-one".