261501153 has 4 divisors (see below), whose sum is σ = 348668208. Its totient is φ = 174334100.

The previous prime is 261501143. The next prime is 261501167. The reversal of 261501153 is 351105162.

261501153 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 261501153 - 2⁹ = 261500641 is a prime.

It is not an unprimeable number, because it can be changed into a prime (261501113) 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, 43583523 + ... + 43583528.

It is an arithmetic number, because the mean of its divisors is an integer number (87167052).

Almost surely, 2^261501153 is an apocalyptic number.

It is an amenable number.

261501153 is a deficient number, since it is larger than the sum of its proper divisors (87167055).

261501153 is an equidigital number, since it uses as much as digits as its factorization.

261501153 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87167054.

The product of its (nonzero) digits is 900, while the sum is 24.

The square root of 261501153 is about 16170.9972790796. The cubic root of 261501153 is about 639.4764215540.

The spelling of 261501153 in words is "two hundred sixty-one million, five hundred one thousand, one hundred fifty-three".