66831904 has 12 divisors (see below), whose sum is σ = 131575374. Its totient is φ = 33415936.

The previous prime is 66831893. The next prime is 66831907. The reversal of 66831904 is 40913866.

It can be written as a sum of positive squares in only one way, i.e., 56972304 + 9859600 = 7548^2 + 3140^2 .

It is not an unprimeable number, because it can be changed into a prime (66831907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1044217 + ... + 1044280.

Almost surely, 2^66831904 is an apocalyptic number.

It is an amenable number.

66831904 is a deficient number, since it is larger than the sum of its proper divisors (64743470).

66831904 is a wasteful number, since it uses less digits than its factorization.

66831904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2088507 (or 2088499 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 37.

The square root of 66831904 is about 8175.0782259254. The cubic root of 66831904 is about 405.8148589238.

The spelling of 66831904 in words is "sixty-six million, eight hundred thirty-one thousand, nine hundred four".