66972644 has 12 divisors (see below), whose sum is σ = 123370800. Its totient is φ = 31723848.

The previous prime is 66972643. The next prime is 66972649. The reversal of 66972644 is 44627966.

It is a junction number, because it is equal to n+sod(n) for n = 66972595 and 66972604.

It is not an unprimeable number, because it can be changed into a prime (66972641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 440534 + ... + 440685.

It is an arithmetic number, because the mean of its divisors is an integer number (10280900).

Almost surely, 2^66972644 is an apocalyptic number.

It is an amenable number.

66972644 is a deficient number, since it is larger than the sum of its proper divisors (56398156).

66972644 is a wasteful number, since it uses less digits than its factorization.

66972644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 881242 (or 881240 counting only the distinct ones).

The product of its digits is 435456, while the sum is 44.

The square root of 66972644 is about 8183.6815676076. The cubic root of 66972644 is about 406.0995250520.

The spelling of 66972644 in words is "sixty-six million, nine hundred seventy-two thousand, six hundred forty-four".