681794261 has 4 divisors (see below), whose sum is σ = 684203712. Its totient is φ = 679384812.

The previous prime is 681794251. The next prime is 681794291. The reversal of 681794261 is 162497186.

681794261 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-681794261 is a prime.

It is a super-2 number, since 2×681794261² = 929686828665072242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681794251) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1204301 + ... + 1204866.

It is an arithmetic number, because the mean of its divisors is an integer number (171050928).

Almost surely, 2^681794261 is an apocalyptic number.

It is an amenable number.

681794261 is a deficient number, since it is larger than the sum of its proper divisors (2409451).

681794261 is a wasteful number, since it uses less digits than its factorization.

681794261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2409450.

The product of its digits is 145152, while the sum is 44.

The square root of 681794261 is about 26111.1903405417. The cubic root of 681794261 is about 880.1386924136.

The spelling of 681794261 in words is "six hundred eighty-one million, seven hundred ninety-four thousand, two hundred sixty-one".