128981715 has 8 divisors (see below), whose sum is σ = 206370768. Its totient is φ = 68790240.

The previous prime is 128981689. The next prime is 128981717. The reversal of 128981715 is 517189821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 128981715 - 2⁸ = 128981459 is a prime.

It is not an unprimeable number, because it can be changed into a prime (128981717) 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, 4299376 + ... + 4299405.

It is an arithmetic number, because the mean of its divisors is an integer number (25796346).

Almost surely, 2^128981715 is an apocalyptic number.

128981715 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

128981715 is a deficient number, since it is larger than the sum of its proper divisors (77389053).

128981715 is an equidigital number, since it uses as much as digits as its factorization.

128981715 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8598789.

The product of its digits is 40320, while the sum is 42.

The square root of 128981715 is about 11357.0117108331. The cubic root of 128981715 is about 505.2535602132.

The spelling of 128981715 in words is "one hundred twenty-eight million, nine hundred eighty-one thousand, seven hundred fifteen".