1321264664560 has 20 divisors (see below), whose sum is σ = 3071940345288. Its totient is φ = 528505865792.

The previous prime is 1321264664513. The next prime is 1321264664581. The reversal of 1321264664560 is 654664621231.

It is a tau number, because it is divible by the number of its divisors (20).

It is a self number, because there is not a number n which added to its sum of digits gives 1321264664560.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8257904074 + ... + 8257904233.

Almost surely, 2^{1321264664560} is an apocalyptic number.

1321264664560 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1321264664560 is an abundant number, since it is smaller than the sum of its proper divisors (1750675680728).

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

1321264664560 is a wasteful number, since it uses less digits than its factorization.

1321264664560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16515808320 (or 16515808314 counting only the distinct ones).

The product of its (nonzero) digits is 1244160, while the sum is 46.

The spelling of 1321264664560 in words is "one trillion, three hundred twenty-one billion, two hundred sixty-four million, six hundred sixty-four thousand, five hundred sixty".