66790686 has 16 divisors (see below), whose sum is σ = 133747200. Its totient is φ = 22235928.

The previous prime is 66790679. The next prime is 66790699. The reversal of 66790686 is 68609766.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1326 + ... + 11633.

It is an arithmetic number, because the mean of its divisors is an integer number (8359200).

Almost surely, 2^66790686 is an apocalyptic number.

66790686 is an abundant number, since it is smaller than the sum of its proper divisors (66956514).

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

66790686 is a wasteful number, since it uses less digits than its factorization.

66790686 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13823.

The product of its (nonzero) digits is 653184, while the sum is 48.

The square root of 66790686 is about 8172.5568826408. The cubic root of 66790686 is about 405.7314141629.

It can be divided in two parts, 66790 and 686, that added together give a palindrome (67476).

The spelling of 66790686 in words is "sixty-six million, seven hundred ninety thousand, six hundred eighty-six".