681279730 has 8 divisors (see below), whose sum is σ = 1226303532. Its totient is φ = 272511888.

The previous prime is 681279721. The next prime is 681279737. The reversal of 681279730 is 37972186.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 673973521 + 7306209 = 25961^2 + 2703^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (681279737) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 34063977 + ... + 34063996.

Almost surely, 2^681279730 is an apocalyptic number.

681279730 is a deficient number, since it is larger than the sum of its proper divisors (545023802).

681279730 is a wasteful number, since it uses less digits than its factorization.

681279730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68127980.

The product of its (nonzero) digits is 127008, while the sum is 43.

The square root of 681279730 is about 26101.3357895721. The cubic root of 681279730 is about 879.9172313683.

The spelling of 681279730 in words is "six hundred eighty-one million, two hundred seventy-nine thousand, seven hundred thirty".