128929966 has 32 divisors (see below), whose sum is σ = 215986176. Its totient is φ = 57228000.

The previous prime is 128929963. The next prime is 128929967. The reversal of 128929966 is 669929821.

It is a super-2 number, since 2×128929966² = 33245872265522312, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128929963) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 256071 + ... + 256573.

It is an arithmetic number, because the mean of its divisors is an integer number (6749568).

Almost surely, 2^128929966 is an apocalyptic number.

128929966 is a deficient number, since it is larger than the sum of its proper divisors (87056210).

128929966 is a wasteful number, since it uses less digits than its factorization.

128929966 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 768.

The product of its digits is 839808, while the sum is 52.

The square root of 128929966 is about 11354.7331980985. The cubic root of 128929966 is about 505.1859799261.

The spelling of 128929966 in words is "one hundred twenty-eight million, nine hundred twenty-nine thousand, nine hundred sixty-six".