681406128 has 80 divisors (see below), whose sum is σ = 2106358240. Its totient is φ = 209661696.

The previous prime is 681406109. The next prime is 681406151. The reversal of 681406128 is 821604186.

681406128 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 2×681406128² = 928628622551904768, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 681406092 and 681406101.

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, 55051 + ... + 66282.

It is an arithmetic number, because the mean of its divisors is an integer number (26329478).

Almost surely, 2^681406128 is an apocalyptic number.

It is an amenable number.

681406128 is an abundant number, since it is smaller than the sum of its proper divisors (1424952112).

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

681406128 is a wasteful number, since it uses less digits than its factorization.

681406128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121363 (or 121351 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 681406128 is about 26103.7569709803. The cubic root of 681406128 is about 879.9716450919.

The spelling of 681406128 in words is "six hundred eighty-one million, four hundred six thousand, one hundred twenty-eight".