261150553 has 4 divisors (see below), whose sum is σ = 261308880. Its totient is φ = 260992228.

The previous prime is 261150521. The next prime is 261150563. The reversal of 261150553 is 355051162.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 261150553 - 2⁵ = 261150521 is a prime.

It is a super-2 number, since 2×261150553² = 136399222664411618, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261150563) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 76663 + ... + 79996.

It is an arithmetic number, because the mean of its divisors is an integer number (65327220).

Almost surely, 2^261150553 is an apocalyptic number.

It is an amenable number.

261150553 is a deficient number, since it is larger than the sum of its proper divisors (158327).

261150553 is a wasteful number, since it uses less digits than its factorization.

261150553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 158326.

The product of its (nonzero) digits is 4500, while the sum is 28.

The square root of 261150553 is about 16160.1532480357. The cubic root of 261150553 is about 639.1905073209.

The spelling of 261150553 in words is "two hundred sixty-one million, one hundred fifty thousand, five hundred fifty-three".