115631381 has 16 divisors (see below), whose sum is σ = 122860800. Its totient is φ = 108662400.

The previous prime is 115631371. The next prime is 115631389. The reversal of 115631381 is 183136511.

It is a cyclic number.

It is not a de Polignac number, because 115631381 - 2¹⁸ = 115369237 is a prime.

It is a super-2 number, since 2×115631381² = 26741232543934322, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (115631389) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 182936 + ... + 183566.

It is an arithmetic number, because the mean of its divisors is an integer number (7678800).

Almost surely, 2^115631381 is an apocalyptic number.

It is an amenable number.

115631381 is a deficient number, since it is larger than the sum of its proper divisors (7229419).

115631381 is an equidigital number, since it uses as much as digits as its factorization.

115631381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 820.

The product of its digits is 2160, while the sum is 29.

The square root of 115631381 is about 10753.2032901829. The cubic root of 115631381 is about 487.1827518198.

Adding to 115631381 its reverse (183136511), we get a palindrome (298767892).

The spelling of 115631381 in words is "one hundred fifteen million, six hundred thirty-one thousand, three hundred eighty-one".