53661607722517 has 4 divisors (see below), whose sum is σ = 53704230128640. Its totient is φ = 53618985316396.

The previous prime is 53661607722511. The next prime is 53661607722521. The reversal of 53661607722517 is 71522770616635.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 53661607722517 - 2⁷ = 53661607722389 is a prime.

It is a super-2 number, since 2×53661607722517² (a number of 28 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (53661607722511) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21311201173 + ... + 21311203690.

It is an arithmetic number, because the mean of its divisors is an integer number (13426057532160).

Almost surely, 2^{53661607722517} is an apocalyptic number.

It is an amenable number.

53661607722517 is a deficient number, since it is larger than the sum of its proper divisors (42622406123).

53661607722517 is a wasteful number, since it uses less digits than its factorization.

53661607722517 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42622406122.

The product of its (nonzero) digits is 22226400, while the sum is 58.

The spelling of 53661607722517 in words is "fifty-three trillion, six hundred sixty-one billion, six hundred seven million, seven hundred twenty-two thousand, five hundred seventeen".