231155613 has 80 divisors (see below), whose sum is σ = 405543600. Its totient is φ = 129890304.

The previous prime is 231155609. The next prime is 231155629. The reversal of 231155613 is 316551132.

231155613 is a `hidden beast` number, since 2 + 31 + 15 + 5 + 613 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 20412324 + 210743289 = 4518^2 + 14517^2 .

It is not a de Polignac number, because 231155613 - 2² = 231155609 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231155633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 662163 + ... + 662511.

It is an arithmetic number, because the mean of its divisors is an integer number (5069295).

Almost surely, 2^231155613 is an apocalyptic number.

It is an amenable number.

231155613 is a deficient number, since it is larger than the sum of its proper divisors (174387987).

231155613 is a wasteful number, since it uses less digits than its factorization.

231155613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 428 (or 419 counting only the distinct ones).

The product of its digits is 2700, while the sum is 27.

The square root of 231155613 is about 15203.8025835644. The cubic root of 231155613 is about 613.7169921259.

The spelling of 231155613 in words is "two hundred thirty-one million, one hundred fifty-five thousand, six hundred thirteen".