66167720 has 16 divisors (see below), whose sum is σ = 148877460. Its totient is φ = 26467072.

The previous prime is 66167693. The next prime is 66167741. The reversal of 66167720 is 2776166.

It can be written as a sum of positive squares in 2 ways, for example, as 56220004 + 9947716 = 7498^2 + 3154^2 .

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, 827057 + ... + 827136.

Almost surely, 2^66167720 is an apocalyptic number.

It is an amenable number.

66167720 is an abundant number, since it is smaller than the sum of its proper divisors (82709740).

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

66167720 is a wasteful number, since it uses less digits than its factorization.

66167720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1654204 (or 1654200 counting only the distinct ones).

The product of its (nonzero) digits is 21168, while the sum is 35.

The square root of 66167720 is about 8134.3543075035. The cubic root of 66167720 is about 404.4660341045.

The spelling of 66167720 in words is "sixty-six million, one hundred sixty-seven thousand, seven hundred twenty".