261227298816 has 315 divisors, whose sum is σ = 830096929207. Its totient is φ = 79159787520.

The previous prime is 261227298809. The next prime is 261227298833. The reversal of 261227298816 is 618892722162.

The square root of 261227298816 is 511104.

It is a perfect power (a square), and thus also a powerful number.

261227298816 is a `hidden beast` number, since 2 + 612 + 2 + 7 + 2 + 9 + 8 + 8 + 16 = 666.

It is a Duffinian number.

Its product of digits (2322432) is a multiple of the sum of its prime divisors (16).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 20 ways as a sum of consecutive naturals, for example, 23747936251 + ... + 23747936261.

Almost surely, 2^261227298816 is an apocalyptic number.

261227298816 is the 511104-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261227298816

261227298816 is an abundant number, since it is smaller than the sum of its proper divisors (568869630391).

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

261227298816 is an frugal number, since it uses more digits than its factorization.

261227298816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100 (or 16 counting only the distinct ones).

The product of its digits is 2322432, while the sum is 54.

The spelling of 261227298816 in words is "two hundred sixty-one billion, two hundred twenty-seven million, two hundred ninety-eight thousand, eight hundred sixteen".