66889975 has 24 divisors (see below), whose sum is σ = 88989840. Its totient is φ = 49720320.

The previous prime is 66889961. The next prime is 66889987. The reversal of 66889975 is 57998866.

It is not a de Polignac number, because 66889975 - 2⁵ = 66889943 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 23847 + ... + 26503.

It is an arithmetic number, because the mean of its divisors is an integer number (3707910).

Almost surely, 2^66889975 is an apocalyptic number.

66889975 is a deficient number, since it is larger than the sum of its proper divisors (22099865).

66889975 is a wasteful number, since it uses less digits than its factorization.

66889975 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2739 (or 2734 counting only the distinct ones).

The product of its digits is 6531840, while the sum is 58.

The square root of 66889975 is about 8178.6291638636. The cubic root of 66889975 is about 405.9323639423.

The spelling of 66889975 in words is "sixty-six million, eight hundred eighty-nine thousand, nine hundred seventy-five".