261698623678800 has 540 divisors, whose sum is σ = 1140837794867680. Its totient is φ = 54378934156800.

The previous prime is 261698623678787. The next prime is 261698623678823. The reversal of 261698623678800 is 8876326896162.

261698623678800 is a `hidden beast` number, since 26 + 169 + 8 + 6 + 2 + 367 + 8 + 80 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 39863470 + ... + 45961869.

Almost surely, 2^{261698623678800} is an apocalyptic number.

261698623678800 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261698623678800 is an abundant number, since it is smaller than the sum of its proper divisors (879139171188880).

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

261698623678800 is a wasteful number, since it uses less digits than its factorization.

261698623678800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85825392 (or 85825367 counting only the distinct ones).

The product of its (nonzero) digits is 501645312, while the sum is 72.

The spelling of 261698623678800 in words is "two hundred sixty-one trillion, six hundred ninety-eight billion, six hundred twenty-three million, six hundred seventy-eight thousand, eight hundred".