128777913915 has 16 divisors (see below), whose sum is σ = 235479614208. Its totient is φ = 58869903456.

The previous prime is 128777913893. The next prime is 128777913931. The reversal of 128777913915 is 519319777821.

It is not a de Polignac number, because 128777913915 - 2¹³ = 128777905723 is a prime.

It is a super-2 number, since 2×128777913915² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 613228057 + ... + 613228266.

It is an arithmetic number, because the mean of its divisors is an integer number (14717475888).

Almost surely, 2^128777913915 is an apocalyptic number.

128777913915 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

128777913915 is a deficient number, since it is larger than the sum of its proper divisors (106701700293).

128777913915 is a wasteful number, since it uses less digits than its factorization.

128777913915 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1226456338.

The product of its digits is 6667920, while the sum is 60.

The spelling of 128777913915 in words is "one hundred twenty-eight billion, seven hundred seventy-seven million, nine hundred thirteen thousand, nine hundred fifteen".