66677656 has 8 divisors (see below), whose sum is σ = 125020620. Its totient is φ = 33338824.

The previous prime is 66677651. The next prime is 66677687. The reversal of 66677656 is 65677666.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66677651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4167346 + ... + 4167361.

Almost surely, 2^66677656 is an apocalyptic number.

It is an amenable number.

66677656 is a deficient number, since it is larger than the sum of its proper divisors (58342964).

66677656 is a wasteful number, since it uses less digits than its factorization.

66677656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8334713 (or 8334709 counting only the distinct ones).

The product of its digits is 1905120, while the sum is 49.

The square root of 66677656 is about 8165.6387380290. The cubic root of 66677656 is about 405.5024115958.

The spelling of 66677656 in words is "sixty-six million, six hundred seventy-seven thousand, six hundred fifty-six".