261507740 has 48 divisors (see below), whose sum is σ = 592741632. Its totient is φ = 96339456.

The previous prime is 261507737. The next prime is 261507751. The reversal of 261507740 is 47705162.

It is a junction number, because it is equal to n+sod(n) for n = 261507697 and 261507706.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 156992 + ... + 158648.

It is an arithmetic number, because the mean of its divisors is an integer number (12348784).

Almost surely, 2^261507740 is an apocalyptic number.

261507740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261507740 is an abundant number, since it is smaller than the sum of its proper divisors (331233892).

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

261507740 is a wasteful number, since it uses less digits than its factorization.

With its predecessor (261507739) it forms an eRAP, since the sums of their prime factors are consecutive (2285 and 2286).

261507740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2286 (or 2284 counting only the distinct ones).

The product of its (nonzero) digits is 11760, while the sum is 32.

The square root of 261507740 is about 16171.2009448897. The cubic root of 261507740 is about 639.4817908048.

The spelling of 261507740 in words is "two hundred sixty-one million, five hundred seven thousand, seven hundred forty".