66404579 has 4 divisors (see below), whose sum is σ = 66595200. Its totient is φ = 66213960.

The previous prime is 66404557. The next prime is 66404581. The reversal of 66404579 is 97540466.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66404579 - 2²⁰ = 65356003 is a prime.

It is a super-2 number, since 2×66404579² = 8819136224334482, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66404549) 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, 94787 + ... + 95484.

It is an arithmetic number, because the mean of its divisors is an integer number (16648800).

Almost surely, 2^66404579 is an apocalyptic number.

66404579 is a deficient number, since it is larger than the sum of its proper divisors (190621).

66404579 is a wasteful number, since it uses less digits than its factorization.

66404579 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 190620.

The product of its (nonzero) digits is 181440, while the sum is 41.

The square root of 66404579 is about 8148.9004779786. The cubic root of 66404579 is about 404.9480784935.

It can be divided in two parts, 6640457 and 9, that added together give a palindrome (6640466).

The spelling of 66404579 in words is "sixty-six million, four hundred four thousand, five hundred seventy-nine".