131121928 has 16 divisors (see below), whose sum is σ = 280975680. Its totient is φ = 56195088.

The previous prime is 131121883. The next prime is 131121929. The reversal of 131121928 is 829121131.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a junction number, because it is equal to n+sod(n) for n = 131121896 and 131121905.

It is not an unprimeable number, because it can be changed into a prime (131121929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1170676 + ... + 1170787.

It is an arithmetic number, because the mean of its divisors is an integer number (17560980).

Almost surely, 2^131121928 is an apocalyptic number.

It is an amenable number.

131121928 is an abundant number, since it is smaller than the sum of its proper divisors (149853752).

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

131121928 is a wasteful number, since it uses less digits than its factorization.

131121928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2341476 (or 2341472 counting only the distinct ones).

The product of its digits is 864, while the sum is 28.

The square root of 131121928 is about 11450.8483528514. The cubic root of 131121928 is about 508.0328269443.

The spelling of 131121928 in words is "one hundred thirty-one million, one hundred twenty-one thousand, nine hundred twenty-eight".