66402979 has 2 divisors, whose sum is σ = 66402980. Its totient is φ = 66402978.

The previous prime is 66402977. The next prime is 66402991. The reversal of 66402979 is 97920466.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66402979 - 2¹ = 66402977 is a prime.

Together with 66402977, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (66402977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33201489 + 33201490.

It is an arithmetic number, because the mean of its divisors is an integer number (33201490).

Almost surely, 2^66402979 is an apocalyptic number.

66402979 is a deficient number, since it is larger than the sum of its proper divisors (1).

66402979 is an equidigital number, since it uses as much as digits as its factorization.

66402979 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 163296, while the sum is 43.

The square root of 66402979 is about 8148.8023046335. The cubic root of 66402979 is about 404.9448260967.

The spelling of 66402979 in words is "sixty-six million, four hundred two thousand, nine hundred seventy-nine".