1231156136 has 32 divisors (see below), whose sum is σ = 2639619840. Its totient is φ = 527352768.

The previous prime is 1231156109. The next prime is 1231156193. The reversal of 1231156136 is 6316511321.

It is a junction number, because it is equal to n+sod(n) for n = 1231156099 and 1231156108.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 123266 + ... + 132878.

It is an arithmetic number, because the mean of its divisors is an integer number (82488120).

Almost surely, 2^1231156136 is an apocalyptic number.

It is an amenable number.

1231156136 is an abundant number, since it is smaller than the sum of its proper divisors (1408463704).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1231156136 is a wasteful number, since it uses less digits than its factorization.

1231156136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11913 (or 11909 counting only the distinct ones).

The product of its digits is 3240, while the sum is 29.

The square root of 1231156136 is about 35087.8345869334. The cubic root of 1231156136 is about 1071.7768642468.

Adding to 1231156136 its reverse (6316511321), we get a palindrome (7547667457).

The spelling of 1231156136 in words is "one billion, two hundred thirty-one million, one hundred fifty-six thousand, one hundred thirty-six".