261431140 has 24 divisors (see below), whose sum is σ = 549343872. Its totient is φ = 104508000.

The previous prime is 261431123. The next prime is 261431141. The reversal of 261431140 is 41134162.

It is not an unprimeable number, because it can be changed into a prime (261431141) 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, 42117 + ... + 47923.

It is an arithmetic number, because the mean of its divisors is an integer number (22889328).

Almost surely, 2^261431140 is an apocalyptic number.

261431140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261431140 is an abundant number, since it is smaller than the sum of its proper divisors (287912732).

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

261431140 is a wasteful number, since it uses less digits than its factorization.

261431140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8067 (or 8065 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 22.

The square root of 261431140 is about 16168.8323635320. The cubic root of 261431140 is about 639.4193463959.

The spelling of 261431140 in words is "two hundred sixty-one million, four hundred thirty-one thousand, one hundred forty".