813772881780 has 24 divisors (see below), whose sum is σ = 2278564069152. Its totient is φ = 217006101792.

The previous prime is 813772881763. The next prime is 813772881869. The reversal of 813772881780 is 87188277318.

It is a Harshad number since it is a multiple of its sum of digits (60), and also a Moran number because the ratio is a prime number: 13562881363 = 813772881780 / (8 + 1 + 3 + 7 + 7 + 2 + 8 + 8 + 1 + 7 + 8 + 0).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6781440622 + ... + 6781440741.

It is an arithmetic number, because the mean of its divisors is an integer number (94940169548).

Almost surely, 2^813772881780 is an apocalyptic number.

It is an amenable number.

813772881780 is an abundant number, since it is smaller than the sum of its proper divisors (1464791187372).

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

813772881780 is a wasteful number, since it uses less digits than its factorization.

813772881780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13562881375 (or 13562881373 counting only the distinct ones).

The product of its (nonzero) digits is 8429568, while the sum is 60.

The spelling of 813772881780 in words is "eight hundred thirteen billion, seven hundred seventy-two million, eight hundred eighty-one thousand, seven hundred eighty".