261869940300816 has 105 divisors (see below), whose sum is σ = 760716598498381. Its totient is φ = 87289397534016.

The previous prime is 261869940300809. The next prime is 261869940300823. The reversal of 261869940300816 is 618003049968162.

The square root of 261869940300816 is 16182396.

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

261869940300816 is a `hidden beast` number, since 2 + 61 + 8 + 6 + 99 + 403 + 0 + 0 + 81 + 6 = 666.

It is an interprime number because it is at equal distance from previous prime (261869940300809) and next prime (261869940300823).

It can be written as a sum of positive squares in only one way, i.e., 256023680547600 + 5846259753216 = 16000740^2 + 2417904^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 20 ways as a sum of consecutive naturals, for example, 1747623850 + ... + 1747773686.

Almost surely, 2^{261869940300816} is an apocalyptic number.

261869940300816 is the 16182396-th square number.

It is an amenable number.

261869940300816 is an abundant number, since it is smaller than the sum of its proper divisors (498846658197565).

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

261869940300816 is an frugal number, since it uses more digits than its factorization.

261869940300816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 299700 (or 149842 counting only the distinct ones).

The product of its (nonzero) digits is 26873856, while the sum is 63.

The spelling of 261869940300816 in words is "two hundred sixty-one trillion, eight hundred sixty-nine billion, nine hundred forty million, three hundred thousand, eight hundred sixteen".