231428921 has 16 divisors (see below), whose sum is σ = 246758400. Its totient is φ = 216586128.

The previous prime is 231428917. The next prime is 231428927. The reversal of 231428921 is 129824132.

It is a cyclic number.

It is not a de Polignac number, because 231428921 - 2² = 231428917 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (231428927) 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, 275420 + ... + 276258.

It is an arithmetic number, because the mean of its divisors is an integer number (15422400).

Almost surely, 2^231428921 is an apocalyptic number.

It is an amenable number.

231428921 is a deficient number, since it is larger than the sum of its proper divisors (15329479).

231428921 is a wasteful number, since it uses less digits than its factorization.

231428921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1108.

The product of its digits is 6912, while the sum is 32.

The square root of 231428921 is about 15212.7880745115. The cubic root of 231428921 is about 613.9587739830.

The spelling of 231428921 in words is "two hundred thirty-one million, four hundred twenty-eight thousand, nine hundred twenty-one".