231621513 has 8 divisors (see below), whose sum is σ = 308987328. Its totient is φ = 154335024.

The previous prime is 231621487. The next prime is 231621527. The reversal of 231621513 is 315126132.

231621513 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 231621513 - 2⁶ = 231621449 is a prime.

It is not an unprimeable number, because it can be changed into a prime (231621563) 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, 12645 + ... + 24962.

It is an arithmetic number, because the mean of its divisors is an integer number (38623416).

Almost surely, 2^231621513 is an apocalyptic number.

It is an amenable number.

231621513 is a deficient number, since it is larger than the sum of its proper divisors (77365815).

231621513 is a wasteful number, since it uses less digits than its factorization.

231621513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39663.

The product of its digits is 1080, while the sum is 24.

The square root of 231621513 is about 15219.1166957876. The cubic root of 231621513 is about 614.1290361418.

Adding to 231621513 its reverse (315126132), we get a palindrome (546747645).

The spelling of 231621513 in words is "two hundred thirty-one million, six hundred twenty-one thousand, five hundred thirteen".