1261637912680 has 64 divisors (see below), whose sum is σ = 2856101472000. Its totient is φ = 501559847424.

The previous prime is 1261637912653. The next prime is 1261637912681. The reversal of 1261637912680 is 862197361621.

It is not an unprimeable number, because it can be changed into a prime (1261637912681) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 82350061 + ... + 82365379.

It is an arithmetic number, because the mean of its divisors is an integer number (44626585500).

Almost surely, 2^{1261637912680} is an apocalyptic number.

1261637912680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1261637912680 is an abundant number, since it is smaller than the sum of its proper divisors (1594463559320).

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

1261637912680 is a wasteful number, since it uses less digits than its factorization.

1261637912680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27826 (or 27822 counting only the distinct ones).

The product of its (nonzero) digits is 1306368, while the sum is 52.

The spelling of 1261637912680 in words is "one trillion, two hundred sixty-one billion, six hundred thirty-seven million, nine hundred twelve thousand, six hundred eighty".