781233128 has 16 divisors (see below), whose sum is σ = 1577490180. Its totient is φ = 360569088.

The previous prime is 781233097. The next prime is 781233163. The reversal of 781233128 is 821332187.

781233128 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 768287524 + 12945604 = 27718^2 + 3598^2 .

It is a super-2 number, since 2×781233128² = 1220650400569328768, which 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, 3755825 + ... + 3756032.

Almost surely, 2^781233128 is an apocalyptic number.

It is an amenable number.

781233128 is an abundant number, since it is smaller than the sum of its proper divisors (796257052).

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

781233128 is a wasteful number, since it uses less digits than its factorization.

781233128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7511876 (or 7511872 counting only the distinct ones).

The product of its digits is 16128, while the sum is 35.

The square root of 781233128 is about 27950.5479016065. The cubic root of 781233128 is about 921.0012445346.

The spelling of 781233128 in words is "seven hundred eighty-one million, two hundred thirty-three thousand, one hundred twenty-eight".