128657620215 has 32 divisors (see below), whose sum is σ = 232474257600. Its totient is φ = 67492517760.

The previous prime is 128657620199. The next prime is 128657620237. The reversal of 128657620215 is 512026756821.

128657620215 is a `hidden beast` number, since 1 + 2 + 8 + 6 + 5 + 7 + 620 + 2 + 15 = 666.

It is not a de Polignac number, because 128657620215 - 2⁴ = 128657620199 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7803400 + ... + 7819869.

It is an arithmetic number, because the mean of its divisors is an integer number (7264820550).

Almost surely, 2^128657620215 is an apocalyptic number.

128657620215 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

128657620215 is a deficient number, since it is larger than the sum of its proper divisors (103816637385).

128657620215 is a wasteful number, since it uses less digits than its factorization.

128657620215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15623344 (or 15623338 counting only the distinct ones).

The product of its (nonzero) digits is 403200, while the sum is 45.

The spelling of 128657620215 in words is "one hundred twenty-eight billion, six hundred fifty-seven million, six hundred twenty thousand, two hundred fifteen".