261420444660 has 96 divisors (see below), whose sum is σ = 758014733952. Its totient is φ = 67275486720.

The previous prime is 261420444511. The next prime is 261420444671. The reversal of 261420444660 is 66444024162.

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, 479854 + ... + 867813.

It is an arithmetic number, because the mean of its divisors is an integer number (7895986812).

Almost surely, 2^261420444660 is an apocalyptic number.

261420444660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261420444660 is an abundant number, since it is smaller than the sum of its proper divisors (496594289292).

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

261420444660 is a wasteful number, since it uses less digits than its factorization.

261420444660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1347793 (or 1347791 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 39.

The spelling of 261420444660 in words is "two hundred sixty-one billion, four hundred twenty million, four hundred forty-four thousand, six hundred sixty".