781121001001020 has 48 divisors (see below), whose sum is σ = 2188722538591008. Its totient is φ = 208148101620480.

The previous prime is 781121001001007. The next prime is 781121001001057. The reversal of 781121001001020 is 20100100121187.

781121001001020 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 2×781121001001020² (a number of 31 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4713415819 + ... + 4713581538.

It is an arithmetic number, because the mean of its divisors is an integer number (45598386220646).

Almost surely, 2^{781121001001020} is an apocalyptic number.

It is an amenable number.

781121001001020 is an abundant number, since it is smaller than the sum of its proper divisors (1407601537589988).

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

781121001001020 is a wasteful number, since it uses less digits than its factorization.

781121001001020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9426998750 (or 9426998748 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 24.

The spelling of 781121001001020 in words is "seven hundred eighty-one trillion, one hundred twenty-one billion, one million, one thousand, twenty".