261740261977920 has 224 divisors, whose sum is σ = 1007303432826240. Its totient is φ = 63452184698880.

The previous prime is 261740261977919. The next prime is 261740261977949. The reversal of 261740261977920 is 29779162047162.

261740261977920 is a `hidden beast` number, since 2 + 6 + 1 + 7 + 4 + 0 + 2 + 619 + 7 + 7 + 9 + 2 + 0 = 666.

261740261977920 is digitally balanced in base 2 and base 4, because in such bases 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 31 ways as a sum of consecutive naturals, for example, 1376905497 + ... + 1377095576.

Almost surely, 2^{261740261977920} is an apocalyptic number.

261740261977920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261740261977920 is an abundant number, since it is smaller than the sum of its proper divisors (745563170848320).

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

261740261977920 is a wasteful number, since it uses less digits than its factorization.

261740261977920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2754001110 (or 2754001094 counting only the distinct ones).

The product of its (nonzero) digits is 32006016, while the sum is 63.

The spelling of 261740261977920 in words is "two hundred sixty-one trillion, seven hundred forty billion, two hundred sixty-one million, nine hundred seventy-seven thousand, nine hundred twenty".