61165017621557 has 4 divisors (see below), whose sum is σ = 61481934811500. Its totient is φ = 60848100431616.

The previous prime is 61165017621511. The next prime is 61165017621569. The reversal of 61165017621557 is 75512671056116.

61165017621557 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 20576829196561 + 40588188424996 = 4536169^2 + 6370886^2 .

It is a cyclic number.

It is not a de Polignac number, because 61165017621557 - 2¹⁰ = 61165017620533 is a prime.

It is a super-2 number, since 2×61165017621557² (a number of 28 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 61165017621499 and 61165017621508.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61165017620557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 158458594682 + ... + 158458595067.

It is an arithmetic number, because the mean of its divisors is an integer number (15370483702875).

Almost surely, 2^{61165017621557} is an apocalyptic number.

It is an amenable number.

61165017621557 is a deficient number, since it is larger than the sum of its proper divisors (316917189943).

61165017621557 is a wasteful number, since it uses less digits than its factorization.

61165017621557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 316917189942.

The product of its (nonzero) digits is 2646000, while the sum is 53.

The spelling of 61165017621557 in words is "sixty-one trillion, one hundred sixty-five billion, seventeen million, six hundred twenty-one thousand, five hundred fifty-seven".