66151221665757 has 32 divisors (see below), whose sum is σ = 89741413555200. Its totient is φ = 43335455974272.

The previous prime is 66151221665741. The next prime is 66151221665759. The reversal of 66151221665757 is 75756612215166.

It is not a de Polignac number, because 66151221665757 - 2⁴ = 66151221665741 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66151221665757.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66151221665759) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 367991544 + ... + 368171262.

It is an arithmetic number, because the mean of its divisors is an integer number (2804419173600).

Almost surely, 2^{66151221665757} is an apocalyptic number.

It is an amenable number.

66151221665757 is a deficient number, since it is larger than the sum of its proper divisors (23590191889443).

66151221665757 is a wasteful number, since it uses less digits than its factorization.

66151221665757 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 186017.

The product of its digits is 31752000, while the sum is 60.

The spelling of 66151221665757 in words is "sixty-six trillion, one hundred fifty-one billion, two hundred twenty-one million, six hundred sixty-five thousand, seven hundred fifty-seven".