128564997 has 8 divisors (see below), whose sum is σ = 187003680. Its totient is φ = 77918160.

The previous prime is 128564993. The next prime is 128565007. The reversal of 128564997 is 799465821.

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

It is not a de Polignac number, because 128564997 - 2² = 128564993 is a prime.

It is a super-2 number, since 2×128564997² = 33057916907220018, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128564993) 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, 1947922 + ... + 1947987.

It is an arithmetic number, because the mean of its divisors is an integer number (23375460).

Almost surely, 2^128564997 is an apocalyptic number.

It is an amenable number.

128564997 is a deficient number, since it is larger than the sum of its proper divisors (58438683).

128564997 is a wasteful number, since it uses less digits than its factorization.

128564997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3895923.

The product of its digits is 1088640, while the sum is 51.

The square root of 128564997 is about 11338.6505810877. The cubic root of 128564997 is about 504.7088437018.

The spelling of 128564997 in words is "one hundred twenty-eight million, five hundred sixty-four thousand, nine hundred ninety-seven".