66969872 has 10 divisors (see below), whose sum is σ = 129754158. Its totient is φ = 33484928.

The previous prime is 66969871. The next prime is 66969893. The reversal of 66969872 is 27896966.

It can be written as a sum of positive squares in only one way, i.e., 63744256 + 3225616 = 7984^2 + 1796^2 .

It is not an unprimeable number, because it can be changed into a prime (66969871) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2092793 + ... + 2092824.

Almost surely, 2^66969872 is an apocalyptic number.

It is an amenable number.

66969872 is a deficient number, since it is larger than the sum of its proper divisors (62784286).

66969872 is a wasteful number, since it uses less digits than its factorization.

66969872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4185625 (or 4185619 counting only the distinct ones).

The product of its digits is 1959552, while the sum is 53.

The square root of 66969872 is about 8183.5122044267. The cubic root of 66969872 is about 406.0939221504.

The spelling of 66969872 in words is "sixty-six million, nine hundred sixty-nine thousand, eight hundred seventy-two".