66397977 has 12 divisors (see below), whose sum is σ = 98139184. Its totient is φ = 43235640.

The previous prime is 66397973. The next prime is 66397979. The reversal of 66397977 is 77979366.

It is not a de Polignac number, because 66397977 - 2² = 66397973 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66397973) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 85399 + ... + 86172.

Almost surely, 2^66397977 is an apocalyptic number.

It is an amenable number.

66397977 is a deficient number, since it is larger than the sum of its proper divisors (31741207).

66397977 is a wasteful number, since it uses less digits than its factorization.

66397977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171620 (or 171617 counting only the distinct ones).

The product of its digits is 3000564, while the sum is 54.

The square root of 66397977 is about 8148.4953825844. The cubic root of 66397977 is about 404.9346579540.

The spelling of 66397977 in words is "sixty-six million, three hundred ninety-seven thousand, nine hundred seventy-seven".