66408372 has 18 divisors (see below), whose sum is σ = 167865698. Its totient is φ = 22136112.

The previous prime is 66408371. The next prime is 66408389. The reversal of 66408372 is 27380466.

66408372 is a `hidden beast` number, since 6 + 640 + 8 + 3 + 7 + 2 = 666.

It can be written as a sum of positive squares in only one way, i.e., 53056656 + 13351716 = 7284^2 + 3654^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 1844677 = 66408372 / (6 + 6 + 4 + 0 + 8 + 3 + 7 + 2).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66408371) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 922303 + ... + 922374.

Almost surely, 2^66408372 is an apocalyptic number.

It is an amenable number.

66408372 is an abundant number, since it is smaller than the sum of its proper divisors (101457326).

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

66408372 is a wasteful number, since it uses less digits than its factorization.

66408372 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1844687 (or 1844682 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 36.

The square root of 66408372 is about 8149.1332054397. The cubic root of 66408372 is about 404.9557884981.

The spelling of 66408372 in words is "sixty-six million, four hundred eight thousand, three hundred seventy-two".