781425819820 has 12 divisors (see below), whose sum is σ = 1640994221664. Its totient is φ = 312570327920.

The previous prime is 781425819809. The next prime is 781425819859. The reversal of 781425819820 is 28918524187.

781425819820 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×781425819820² (a number of 25 digits) contains 22 as substring.

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, 19535645476 + ... + 19535645515.

It is an arithmetic number, because the mean of its divisors is an integer number (136749518472).

Almost surely, 2^781425819820 is an apocalyptic number.

It is an amenable number.

781425819820 is an abundant number, since it is smaller than the sum of its proper divisors (859568401844).

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

781425819820 is a wasteful number, since it uses less digits than its factorization.

781425819820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39071291000 (or 39071290998 counting only the distinct ones).

The product of its (nonzero) digits is 2580480, while the sum is 55.

The spelling of 781425819820 in words is "seven hundred eighty-one billion, four hundred twenty-five million, eight hundred nineteen thousand, eight hundred twenty".