66917960 has 16 divisors (see below), whose sum is σ = 150565500. Its totient is φ = 26767168.

The previous prime is 66917947. The next prime is 66917987. The reversal of 66917960 is 6971966.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 66814276 + 103684 = 8174^2 + 322^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 836435 + ... + 836514.

Almost surely, 2^66917960 is an apocalyptic number.

It is an amenable number.

66917960 is an abundant number, since it is smaller than the sum of its proper divisors (83647540).

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

66917960 is a wasteful number, since it uses less digits than its factorization.

66917960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1672960 (or 1672956 counting only the distinct ones).

The product of its (nonzero) digits is 122472, while the sum is 44.

The square root of 66917960 is about 8180.3398462411. The cubic root of 66917960 is about 405.9889665116.

The spelling of 66917960 in words is "sixty-six million, nine hundred seventeen thousand, nine hundred sixty".