261217921460 has 48 divisors (see below), whose sum is σ = 551723840640. Its totient is φ = 103885676160.

The previous prime is 261217921417. The next prime is 261217921477. The reversal of 261217921460 is 64129712162.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2592137 + ... + 2691023.

It is an arithmetic number, because the mean of its divisors is an integer number (11494246680).

Almost surely, 2^261217921460 is an apocalyptic number.

261217921460 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261217921460 is an abundant number, since it is smaller than the sum of its proper divisors (290505919180).

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

261217921460 is a wasteful number, since it uses less digits than its factorization.

261217921460 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99656 (or 99654 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 41.

The spelling of 261217921460 in words is "two hundred sixty-one billion, two hundred seventeen million, nine hundred twenty-one thousand, four hundred sixty".