66915072 has 180 divisors, whose sum is σ = 228527376. Its totient is φ = 19077120.

The previous prime is 66915061. The next prime is 66915089. The reversal of 66915072 is 27051966.

66915072 is a `hidden beast` number, since 66 + 91 + 507 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 144922 + ... + 145382.

Almost surely, 2^66915072 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66915072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (114263688).

66915072 is an abundant number, since it is smaller than the sum of its proper divisors (161612304).

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

66915072 is an equidigital number, since it uses as much as digits as its factorization.

66915072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 496 (or 473 counting only the distinct ones).

The product of its (nonzero) digits is 22680, while the sum is 36.

The square root of 66915072 is about 8180.1633235529. The cubic root of 66915072 is about 405.9831259620.

The spelling of 66915072 in words is "sixty-six million, nine hundred fifteen thousand, seventy-two".