66557886 has 8 divisors (see below), whose sum is σ = 133115784. Its totient is φ = 22185960.

The previous prime is 66557833. The next prime is 66557903. The reversal of 66557886 is 68875566.

It is a sphenic number, since it is the product of 3 distinct primes.

66557886 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5546485 + ... + 5546496.

It is an arithmetic number, because the mean of its divisors is an integer number (16639473).

Almost surely, 2^66557886 is an apocalyptic number.

66557886 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

66557886 is a wasteful number, since it uses less digits than its factorization.

66557886 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11092986.

The product of its digits is 2419200, while the sum is 51.

The square root of 66557886 is about 8158.3016614979. The cubic root of 66557886 is about 405.2594709799.

It can be divided in two parts, 6655 and 7886, that added together give a palindrome (14541).

The spelling of 66557886 in words is "sixty-six million, five hundred fifty-seven thousand, eight hundred eighty-six".