61165110056581 has 8 divisors (see below), whose sum is σ = 63274623561720. Its totient is φ = 59055621336768.

The previous prime is 61165110056551. The next prime is 61165110056627. The reversal of 61165110056581 is 18565001156116.

It can be written as a sum of positive squares in 4 ways, for example, as 4627252721025 + 56537857335556 = 2151105^2 + 7519166^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 61165110056581 - 2³⁵ = 61130750318213 is a prime.

It is a super-2 number, since 2×61165110056581² (a number of 28 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61165110056551) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1104706 + ... + 11115331.

It is an arithmetic number, because the mean of its divisors is an integer number (7909327945215).

Almost surely, 2^{61165110056581} is an apocalyptic number.

It is an amenable number.

61165110056581 is a deficient number, since it is larger than the sum of its proper divisors (2109513505139).

61165110056581 is a wasteful number, since it uses less digits than its factorization.

61165110056581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12392663.

The product of its (nonzero) digits is 216000, while the sum is 46.

The spelling of 61165110056581 in words is "sixty-one trillion, one hundred sixty-five billion, one hundred ten million, fifty-six thousand, five hundred eighty-one".