261706236464400 has 480 divisors, whose sum is σ = 1039216649210880. Its totient is φ = 54819891210240.

The previous prime is 261706236464389. The next prime is 261706236464401. The reversal of 261706236464400 is 4464632607162.

It is not an unprimeable number, because it can be changed into a prime (261706236464401) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 6558019 + ... + 23799581.

It is an arithmetic number, because the mean of its divisors is an integer number (2165034685856).

Almost surely, 2^{261706236464400} is an apocalyptic number.

261706236464400 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 261706236464400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (519608324605440).

261706236464400 is an abundant number, since it is smaller than the sum of its proper divisors (777510412746480).

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

261706236464400 is a wasteful number, since it uses less digits than its factorization.

261706236464400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17241743 (or 17241732 counting only the distinct ones).

The product of its (nonzero) digits is 6967296, while the sum is 51.

The spelling of 261706236464400 in words is "two hundred sixty-one trillion, seven hundred six billion, two hundred thirty-six million, four hundred sixty-four thousand, four hundred".