66631513055 has 16 divisors (see below), whose sum is σ = 82752443424. Its totient is φ = 51468933120.

The previous prime is 66631513043. The next prime is 66631513099. The reversal of 66631513055 is 55031513666.

It is a happy number.

It is not a de Polignac number, because 66631513055 - 2¹⁴ = 66631496671 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is a Duffinian number.

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, 1655537 + ... + 1695306.

It is an arithmetic number, because the mean of its divisors is an integer number (5172027714).

Almost surely, 2^66631513055 is an apocalyptic number.

66631513055 is a deficient number, since it is larger than the sum of its proper divisors (16120930369).

66631513055 is a wasteful number, since it uses less digits than its factorization.

66631513055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3350986.

The product of its (nonzero) digits is 243000, while the sum is 41.

The spelling of 66631513055 in words is "sixty-six billion, six hundred thirty-one million, five hundred thirteen thousand, fifty-five".