66617231615 has 16 divisors (see below), whose sum is σ = 91797909120. Its totient is φ = 45898953120.

The previous prime is 66617231591. The next prime is 66617231621. The reversal of 66617231615 is 51613271666.

It is not a de Polignac number, because 66617231615 - 2²² = 66613037311 is a prime.

It is a congruent number.

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, 31873229 + ... + 31875318.

It is an arithmetic number, because the mean of its divisors is an integer number (5737369320).

Almost surely, 2^66617231615 is an apocalyptic number.

66617231615 is a deficient number, since it is larger than the sum of its proper divisors (25180677505).

66617231615 is a wasteful number, since it uses less digits than its factorization.

66617231615 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63748582.

The product of its digits is 272160, while the sum is 44.

The spelling of 66617231615 in words is "sixty-six billion, six hundred seventeen million, two hundred thirty-one thousand, six hundred fifteen".