66974809 has 8 divisors (see below), whose sum is σ = 73297728. Its totient is φ = 60690960.

The previous prime is 66974807. The next prime is 66974821. The reversal of 66974809 is 90847966.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 66974809 - 2¹ = 66974807 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66974807) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6117 + ... + 13090.

It is an arithmetic number, because the mean of its divisors is an integer number (9162216).

Almost surely, 2^66974809 is an apocalyptic number.

It is an amenable number.

66974809 is a deficient number, since it is larger than the sum of its proper divisors (6322919).

66974809 is a wasteful number, since it uses less digits than its factorization.

66974809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19535.

The product of its (nonzero) digits is 653184, while the sum is 49.

The square root of 66974809 is about 8183.8138419688. The cubic root of 66974809 is about 406.1039009482.

The spelling of 66974809 in words is "sixty-six million, nine hundred seventy-four thousand, eight hundred nine".