66687572 has 24 divisors (see below), whose sum is σ = 137679360. Its totient is φ = 27658080.

The previous prime is 66687553. The next prime is 66687581. The reversal of 66687572 is 27578666.

It is a Smith number, since the sum of its digits (47) coincides with the sum of the digits of its prime factors.

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, 37547 + ... + 39282.

It is an arithmetic number, because the mean of its divisors is an integer number (5736640).

Almost surely, 2^66687572 is an apocalyptic number.

66687572 is a gapful number since it is divisible by the number (62) formed by its first and last digit.

It is an amenable number.

66687572 is an abundant number, since it is smaller than the sum of its proper divisors (70991788).

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

66687572 is a wasteful number, since it uses less digits than its factorization.

66687572 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76871 (or 76869 counting only the distinct ones).

The product of its digits is 846720, while the sum is 47.

The square root of 66687572 is about 8166.2458939221. The cubic root of 66687572 is about 405.5225120955.

The spelling of 66687572 in words is "sixty-six million, six hundred eighty-seven thousand, five hundred seventy-two".