66557036 has 48 divisors (see below), whose sum is σ = 145146624. Its totient is φ = 26001216.

The previous prime is 66557021. The next prime is 66557047. The reversal of 66557036 is 63075566.

It is a super-2 number, since 2×66557036² = 8859678082210592, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 29111 + ... + 31313.

It is an arithmetic number, because the mean of its divisors is an integer number (3023888).

Almost surely, 2^66557036 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 66557036, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72573312).

66557036 is an abundant number, since it is smaller than the sum of its proper divisors (78589588).

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

66557036 is a wasteful number, since it uses less digits than its factorization.

66557036 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2310 (or 2308 counting only the distinct ones).

The product of its (nonzero) digits is 113400, while the sum is 38.

The square root of 66557036 is about 8158.2495671559. The cubic root of 66557036 is about 405.2577458048.

The spelling of 66557036 in words is "sixty-six million, five hundred fifty-seven thousand, thirty-six".