66747972 has 24 divisors (see below), whose sum is σ = 155879136. Its totient is φ = 22230208.

The previous prime is 66747871. The next prime is 66747973. The reversal of 66747972 is 27974766.

It is a happy number.

It is a super-2 number, since 2×66747972² = 8910583532225568, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66747973) 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, 22648 + ... + 25424.

It is an arithmetic number, because the mean of its divisors is an integer number (6494964).

Almost surely, 2^66747972 is an apocalyptic number.

It is an amenable number.

66747972 is an abundant number, since it is smaller than the sum of its proper divisors (89131164).

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

66747972 is a wasteful number, since it uses less digits than its factorization.

66747972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4787 (or 4785 counting only the distinct ones).

The product of its digits is 889056, while the sum is 48.

The square root of 66747972 is about 8169.9432066569. The cubic root of 66747972 is about 405.6449045592.

The spelling of 66747972 in words is "sixty-six million, seven hundred forty-seven thousand, nine hundred seventy-two".