681399026 has 16 divisors (see below), whose sum is σ = 1274304960. Its totient is φ = 265480080.

The previous prime is 681399007. The next prime is 681399031. The reversal of 681399026 is 620993186.

681399026 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-3 number, since 3×681399026³ (a number of 27 digits) contains 333 as substring.

It is a Curzon 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, 2212181 + ... + 2212488.

It is an arithmetic number, because the mean of its divisors is an integer number (79644060).

Almost surely, 2^681399026 is an apocalyptic number.

681399026 is a deficient number, since it is larger than the sum of its proper divisors (592905934).

681399026 is a wasteful number, since it uses less digits than its factorization.

681399026 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4424689.

The product of its (nonzero) digits is 139968, while the sum is 44.

The square root of 681399026 is about 26103.6209365674. The cubic root of 681399026 is about 879.9685878939.

The spelling of 681399026 in words is "six hundred eighty-one million, three hundred ninety-nine thousand, twenty-six".