261510140 has 24 divisors (see below), whose sum is σ = 554308272. Its totient is φ = 103625600.

The previous prime is 261510127. The next prime is 261510149. The reversal of 261510140 is 41015162.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261510149) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 58961 + ... + 63240.

It is an arithmetic number, because the mean of its divisors is an integer number (23096178).

Almost surely, 2^261510140 is an apocalyptic number.

261510140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261510140 is an abundant number, since it is smaller than the sum of its proper divisors (292798132).

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

261510140 is a wasteful number, since it uses less digits than its factorization.

261510140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122317 (or 122315 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 20.

The square root of 261510140 is about 16171.2751507109. The cubic root of 261510140 is about 639.4837470905.

The spelling of 261510140 in words is "two hundred sixty-one million, five hundred ten thousand, one hundred forty".