66973520 has 40 divisors (see below), whose sum is σ = 156425256. Its totient is φ = 26667008.

The previous prime is 66973507. The next prime is 66973573. The reversal of 66973520 is 2537966.

It can be written as a sum of positive squares in 4 ways, for example, as 322624 + 66650896 = 568^2 + 8164^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16844 + ... + 20436.

Almost surely, 2^66973520 is an apocalyptic number.

It is an amenable number.

66973520 is an abundant number, since it is smaller than the sum of its proper divisors (89451736).

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

66973520 is a wasteful number, since it uses less digits than its factorization.

66973520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3839 (or 3833 counting only the distinct ones).

The product of its (nonzero) digits is 68040, while the sum is 38.

The square root of 66973520 is about 8183.7350885766. The cubic root of 66973520 is about 406.1012956338.

The spelling of 66973520 in words is "sixty-six million, nine hundred seventy-three thousand, five hundred twenty".