261727920 has 120 divisors (see below), whose sum is σ = 930717216. Its totient is φ = 65685504.

The previous prime is 261727919. The next prime is 261727927. The reversal of 261727920 is 29727162.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (261727927) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1549 + ... + 22931.

Almost surely, 2^261727920 is an apocalyptic number.

261727920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261727920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (465358608).

261727920 is an abundant number, since it is smaller than the sum of its proper divisors (668989296).

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

261727920 is a wasteful number, since it uses less digits than its factorization.

261727920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21419 (or 21410 counting only the distinct ones).

The product of its (nonzero) digits is 21168, while the sum is 36.

The square root of 261727920 is about 16178.0072938542. The cubic root of 261727920 is about 639.6612139233.

The spelling of 261727920 in words is "two hundred sixty-one million, seven hundred twenty-seven thousand, nine hundred twenty".