66380388 has 24 divisors (see below), whose sum is σ = 155172192. Its totient is φ = 22086144.

The previous prime is 66380387. The next prime is 66380399. The reversal of 66380388 is 88308366.

It is a super-2 number, since 2×66380388² = 8812711822061088, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66380387) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2131 + ... + 11717.

It is an arithmetic number, because the mean of its divisors is an integer number (6465508).

Almost surely, 2^66380388 is an apocalyptic number.

It is an amenable number.

66380388 is an abundant number, since it is smaller than the sum of its proper divisors (88791804).

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

66380388 is a wasteful number, since it uses less digits than its factorization.

66380388 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10171 (or 10169 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 42.

The square root of 66380388 is about 8147.4160320926. The cubic root of 66380388 is about 404.8988987084.

The spelling of 66380388 in words is "sixty-six million, three hundred eighty thousand, three hundred eighty-eight".