128957836 has 24 divisors (see below), whose sum is σ = 258279840. Its totient is φ = 55189632.

The previous prime is 128957831. The next prime is 128957837. The reversal of 128957836 is 638759821.

It is a hoax number, since the sum of its digits (49) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 128957836.

It is not an unprimeable number, because it can be changed into a prime (128957831) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19806 + ... + 25498.

It is an arithmetic number, because the mean of its divisors is an integer number (10761660).

Almost surely, 2^128957836 is an apocalyptic number.

It is an amenable number.

128957836 is an abundant number, since it is smaller than the sum of its proper divisors (129322004).

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

128957836 is a wasteful number, since it uses less digits than its factorization.

128957836 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6513 (or 6511 counting only the distinct ones).

The product of its digits is 725760, while the sum is 49.

The square root of 128957836 is about 11355.9603733018. The cubic root of 128957836 is about 505.2223782885. Note that the first 3 decimals are identical.

The spelling of 128957836 in words is "one hundred twenty-eight million, nine hundred fifty-seven thousand, eight hundred thirty-six".