261894124800 has 1404 divisors, whose sum is σ = 1212271430496. Its totient is φ = 54419558400.

The previous prime is 261894124799. The next prime is 261894124829. The reversal of 261894124800 is 8421498162.

261894124800 is a `hidden beast` number, since 2 + 618 + 9 + 4 + 1 + 24 + 8 + 0 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 155 ways as a sum of consecutive naturals, for example, 23808556795 + ... + 23808556805.

Almost surely, 2^261894124800 is an apocalyptic number.

261894124800 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 261894124800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (606135715248).

261894124800 is an abundant number, since it is smaller than the sum of its proper divisors (950377305696).

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

261894124800 is an frugal number, since it uses more digits than its factorization.

261894124800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80 (or 28 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 45.

The spelling of 261894124800 in words is "two hundred sixty-one billion, eight hundred ninety-four million, one hundred twenty-four thousand, eight hundred".