66437500 has 42 divisors (see below), whose sum is σ = 145466888. Its totient is φ = 26550000.

The previous prime is 66437467. The next prime is 66437549. The reversal of 66437500 is 573466.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 61969 + ... + 63031.

Almost surely, 2^66437500 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 66437500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72733444).

66437500 is an abundant number, since it is smaller than the sum of its proper divisors (79029388).

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

66437500 is an equidigital number, since it uses as much as digits as its factorization.

66437500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1097 (or 1070 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 31.

The square root of 66437500 is about 8150.9201934506. The cubic root of 66437500 is about 405.0149869981.

The spelling of 66437500 in words is "sixty-six million, four hundred thirty-seven thousand, five hundred".