66879907 has 4 divisors (see below), whose sum is σ = 66905080. Its totient is φ = 66854736.

The previous prime is 66879889. The next prime is 66879937. The reversal of 66879907 is 70997866.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 70997866 = 2 ⋅35498933.

It is a cyclic number.

It is not a de Polignac number, because 66879907 - 2⁷ = 66879779 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66879937) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8058 + ... + 14095.

It is an arithmetic number, because the mean of its divisors is an integer number (16726270).

Almost surely, 2^66879907 is an apocalyptic number.

66879907 is a deficient number, since it is larger than the sum of its proper divisors (25173).

66879907 is a wasteful number, since it uses less digits than its factorization.

66879907 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25172.

The product of its (nonzero) digits is 1143072, while the sum is 52.

The square root of 66879907 is about 8178.0136341290. The cubic root of 66879907 is about 405.9119965051.

The spelling of 66879907 in words is "sixty-six million, eight hundred seventy-nine thousand, nine hundred seven".