261790720 has 44 divisors (see below), whose sum is σ = 628003224. Its totient is φ = 104714240.

The previous prime is 261790709. The next prime is 261790723. The reversal of 261790720 is 27097162.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261790723) 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, 20446 + ... + 30685.

Almost surely, 2^261790720 is an apocalyptic number.

261790720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261790720 is an abundant number, since it is smaller than the sum of its proper divisors (366212504).

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

261790720 is an equidigital number, since it uses as much as digits as its factorization.

261790720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51156 (or 51138 counting only the distinct ones).

The product of its (nonzero) digits is 10584, while the sum is 34.

The square root of 261790720 is about 16179.9480839711. The cubic root of 261790720 is about 639.7123707528.

The spelling of 261790720 in words is "two hundred sixty-one million, seven hundred ninety thousand, seven hundred twenty".