66656511 has 12 divisors (see below), whose sum is σ = 96354960. Its totient is φ = 44403840.

The previous prime is 66656483. The next prime is 66656531. The reversal of 66656511 is 11565666.

It is not a de Polignac number, because 66656511 - 2⁹ = 66655999 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66656531) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16950 + ... + 20508.

It is an arithmetic number, because the mean of its divisors is an integer number (8029580).

Almost surely, 2^66656511 is an apocalyptic number.

66656511 is a deficient number, since it is larger than the sum of its proper divisors (29698449).

66656511 is a wasteful number, since it uses less digits than its factorization.

66656511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5646 (or 5643 counting only the distinct ones).

The product of its digits is 32400, while the sum is 36.

The square root of 66656511 is about 8164.3438805577. The cubic root of 66656511 is about 405.4595423873.

The spelling of 66656511 in words is "sixty-six million, six hundred fifty-six thousand, five hundred eleven".