231540015 has 32 divisors (see below), whose sum is σ = 424037376. Its totient is φ = 105684480.

The previous prime is 231539999. The next prime is 231540019. The reversal of 231540015 is 510045132.

It is not a de Polignac number, because 231540015 - 2⁴ = 231539999 is a prime.

It is a super-2 number, since 2×231540015² = 107221557092400450, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a junction number, because it is equal to n+sod(n) for n = 231539973 and 231540000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231540019) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 91254 + ... + 93756.

It is an arithmetic number, because the mean of its divisors is an integer number (13251168).

Almost surely, 2^231540015 is an apocalyptic number.

231540015 is a deficient number, since it is larger than the sum of its proper divisors (192497361).

231540015 is a wasteful number, since it uses less digits than its factorization.

231540015 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3399.

The product of its (nonzero) digits is 600, while the sum is 21.

The square root of 231540015 is about 15216.4389723746. The cubic root of 231540015 is about 614.0569988500.

Adding to 231540015 its reverse (510045132), we get a palindrome (741585147).

The spelling of 231540015 in words is "two hundred thirty-one million, five hundred forty thousand, fifteen".