66039974 has 32 divisors (see below), whose sum is σ = 133007616. Its totient is φ = 23749920.

The previous prime is 66039947. The next prime is 66039979. The reversal of 66039974 is 47993066.

It is a super-2 number, since 2×66039974² = 8722556331841352, which contains 22 as substring.

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66039979) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14492 + ... + 18495.

It is an arithmetic number, because the mean of its divisors is an integer number (4156488).

Almost surely, 2^66039974 is an apocalyptic number.

66039974 is an abundant number, since it is smaller than the sum of its proper divisors (66967642).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66039974 is a wasteful number, since it uses less digits than its factorization.

66039974 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33020.

The product of its (nonzero) digits is 244944, while the sum is 44.

The square root of 66039974 is about 8126.4982618592. The cubic root of 66039974 is about 404.2055737418.

The spelling of 66039974 in words is "sixty-six million, thirty-nine thousand, nine hundred seventy-four".