261565165502031 has 8 divisors (see below), whose sum is σ = 348753783975984. Its totient is φ = 174376662014720.

The previous prime is 261565165502009. The next prime is 261565165502059. The reversal of 261565165502031 is 130205561565162.

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 261565165502031 - 2⁷ = 261565165501903 is a prime.

It is a super-2 number, since 2×261565165502031² (a number of 30 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261565165502831) 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, 23291010 + ... + 32643551.

It is an arithmetic number, because the mean of its divisors is an integer number (43594222996998).

Almost surely, 2^{261565165502031} is an apocalyptic number.

261565165502031 is a deficient number, since it is larger than the sum of its proper divisors (87188618473953).

261565165502031 is a wasteful number, since it uses less digits than its factorization.

261565165502031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57493321.

The product of its (nonzero) digits is 1620000, while the sum is 48.

The spelling of 261565165502031 in words is "two hundred sixty-one trillion, five hundred sixty-five billion, one hundred sixty-five million, five hundred two thousand, thirty-one".