781123020 has 24 divisors (see below), whose sum is σ = 2187144624. Its totient is φ = 208299456.

The previous prime is 781123019. The next prime is 781123037. The reversal of 781123020 is 20321187.

It is a super-2 number, since 2×781123020² = 1220306344747840800, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6509299 + ... + 6509418.

It is an arithmetic number, because the mean of its divisors is an integer number (91131026).

Almost surely, 2^781123020 is an apocalyptic number.

It is an amenable number.

781123020 is an abundant number, since it is smaller than the sum of its proper divisors (1406021604).

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

781123020 is a wasteful number, since it uses less digits than its factorization.

781123020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13018729 (or 13018727 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 24.

The square root of 781123020 is about 27948.5781391469. The cubic root of 781123020 is about 920.9579734690.

The spelling of 781123020 in words is "seven hundred eighty-one million, one hundred twenty-three thousand, twenty".