261282009616920 has 192 divisors, whose sum is σ = 894221890848000. Its totient is φ = 65981325959424.

The previous prime is 261282009616889. The next prime is 261282009616961. The reversal of 261282009616920 is 29616900282162.

261282009616920 is a `hidden beast` number, since 2 + 6 + 12 + 8 + 2 + 0 + 0 + 9 + 616 + 9 + 2 + 0 = 666.

261282009616920 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 9132261 + ... + 24616299.

It is an arithmetic number, because the mean of its divisors is an integer number (4657405681500).

Almost surely, 2^{261282009616920} is an apocalyptic number.

261282009616920 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 261282009616920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (447110945424000).

261282009616920 is an abundant number, since it is smaller than the sum of its proper divisors (632939881231080).

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

261282009616920 is a wasteful number, since it uses less digits than its factorization.

261282009616920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15486542 (or 15486535 counting only the distinct ones).

The product of its (nonzero) digits is 2239488, while the sum is 54.

The spelling of 261282009616920 in words is "two hundred sixty-one trillion, two hundred eighty-two billion, nine million, six hundred sixteen thousand, nine hundred twenty".