261552403011455 has 4 divisors (see below), whose sum is σ = 313862883613752. Its totient is φ = 209241922409160.

The previous prime is 261552403011413. The next prime is 261552403011461. The reversal of 261552403011455 is 554110304255162.

It is a happy number.

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

It is not a de Polignac number, because 261552403011455 - 2⁴² = 257154356500351 is a prime.

It is a super-2 number, since 2×261552403011455² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26155240301141 + ... + 26155240301150.

It is an arithmetic number, because the mean of its divisors is an integer number (78465720903438).

Almost surely, 2^{261552403011455} is an apocalyptic number.

261552403011455 is a deficient number, since it is larger than the sum of its proper divisors (52310480602297).

261552403011455 is an equidigital number, since it uses as much as digits as its factorization.

261552403011455 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52310480602296.

The product of its (nonzero) digits is 720000, while the sum is 44.

The spelling of 261552403011455 in words is "two hundred sixty-one trillion, five hundred fifty-two billion, four hundred three million, eleven thousand, four hundred fifty-five".