66977966 has 16 divisors (see below), whose sum is σ = 109738368. Its totient is φ = 30406200.

The previous prime is 66977959. The next prime is 66978007.

It is a happy number.

66977966 is nontrivially palindromic in base 10.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23351 + ... + 26061.

It is an arithmetic number, because the mean of its divisors is an integer number (6858648).

Almost surely, 2^66977966 is an apocalyptic number.

66977966 is a deficient number, since it is larger than the sum of its proper divisors (42760402).

66977966 is a wasteful number, since it uses less digits than its factorization.

66977966 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3847.

The product of its digits is 5143824, while the sum is 56.

The square root of 66977966 is about 8184.0067204273. The cubic root of 66977966 is about 406.1102817048.

The spelling of 66977966 in words is "sixty-six million, nine hundred seventy-seven thousand, nine hundred sixty-six".