261154253465 has 16 divisors (see below), whose sum is σ = 370504558080. Its totient is φ = 172902125760.

The previous prime is 261154253447. The next prime is 261154253489. The reversal of 261154253465 is 564352451162.

It is not a de Polignac number, because 261154253465 - 2⁶ = 261154253401 is a prime.

It is a super-3 number, since 3×261154253465³ (a number of 35 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 128646401 + ... + 128648430.

It is an arithmetic number, because the mean of its divisors is an integer number (23156534880).

Almost surely, 2^261154253465 is an apocalyptic number.

It is an amenable number.

261154253465 is a deficient number, since it is larger than the sum of its proper divisors (109350304615).

261154253465 is a wasteful number, since it uses less digits than its factorization.

261154253465 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 257294872.

The product of its digits is 864000, while the sum is 44.

The spelling of 261154253465 in words is "two hundred sixty-one billion, one hundred fifty-four million, two hundred fifty-three thousand, four hundred sixty-five".