681765460 has 24 divisors (see below), whose sum is σ = 1439625096. Its totient is φ = 271198080.

The previous prime is 681765457. The next prime is 681765479. The reversal of 681765460 is 64567186.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 868624 + 680896836 = 932^2 + 26094^2 .

It is a hoax number, since the sum of its digits (43) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 90547 + ... + 97786.

It is an arithmetic number, because the mean of its divisors is an integer number (59984379).

Almost surely, 2^681765460 is an apocalyptic number.

It is an amenable number.

681765460 is an abundant number, since it is smaller than the sum of its proper divisors (757859636).

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

681765460 is a wasteful number, since it uses less digits than its factorization.

681765460 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 188523 (or 188521 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 43.

The square root of 681765460 is about 26110.6388278801. The cubic root of 681765460 is about 880.1262990213.

The spelling of 681765460 in words is "six hundred eighty-one million, seven hundred sixty-five thousand, four hundred sixty".