261591102 has 24 divisors (see below), whose sum is σ = 579963384. Its totient is φ = 85168944.

The previous prime is 261591101. The next prime is 261591131. The reversal of 261591102 is 201195162.

261591102 is a `hidden beast` number, since 2 + 61 + 591 + 10 + 2 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261591101) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 168213 + ... + 169760.

It is an arithmetic number, because the mean of its divisors is an integer number (24165141).

Almost surely, 2^261591102 is an apocalyptic number.

261591102 is an abundant number, since it is smaller than the sum of its proper divisors (318372282).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261591102 is a wasteful number, since it uses less digits than its factorization.

261591102 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 338024 (or 338021 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 27.

The square root of 261591102 is about 16173.7782227901. The cubic root of 261591102 is about 639.5497337492.

It can be divided in two parts, 26159 and 1102, that added together give a triangular number (27261 = T₂₃₃).

The spelling of 261591102 in words is "two hundred sixty-one million, five hundred ninety-one thousand, one hundred two".