681121780 has 24 divisors (see below), whose sum is σ = 1444521960. Its totient is φ = 269750400.

The previous prime is 681121769. The next prime is 681121829. The reversal of 681121780 is 87121186.

681121780 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 4 ways, for example, as 68757264 + 612364516 = 8292^2 + 24746^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 166575 + ... + 170614.

It is an arithmetic number, because the mean of its divisors is an integer number (60188415).

Almost surely, 2^681121780 is an apocalyptic number.

It is an amenable number.

681121780 is an abundant number, since it is smaller than the sum of its proper divisors (763400180).

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

681121780 is a wasteful number, since it uses less digits than its factorization.

681121780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 337299 (or 337297 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 34.

The square root of 681121780 is about 26098.3099069652. The cubic root of 681121780 is about 879.8492252015.

The spelling of 681121780 in words is "six hundred eighty-one million, one hundred twenty-one thousand, seven hundred eighty".