261080400 has 120 divisors (see below), whose sum is σ = 955833664. Its totient is φ = 59673600.

The previous prime is 261080353. The next prime is 261080423. The reversal of 261080400 is 4080162.

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 (21).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7141 + ... + 23940.

Almost surely, 2^261080400 is an apocalyptic number.

261080400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261080400 is an abundant number, since it is smaller than the sum of its proper divisors (694753264).

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

261080400 is a wasteful number, since it uses less digits than its factorization.

261080400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31109 (or 31098 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 21.

The square root of 261080400 is about 16157.9825473355. The cubic root of 261080400 is about 639.1332668428.

The spelling of 261080400 in words is "two hundred sixty-one million, eighty thousand, four hundred".