681055951 has 4 divisors (see below), whose sum is σ = 681680152. Its totient is φ = 680431752.

The previous prime is 681055933. The next prime is 681055979. The reversal of 681055951 is 159550186.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 681055951 - 2⁹ = 681055439 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681055901) 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, 310461 + ... + 312646.

It is an arithmetic number, because the mean of its divisors is an integer number (170420038).

Almost surely, 2^681055951 is an apocalyptic number.

681055951 is a deficient number, since it is larger than the sum of its proper divisors (624201).

681055951 is a wasteful number, since it uses less digits than its factorization.

681055951 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 624200.

The product of its (nonzero) digits is 54000, while the sum is 40.

The square root of 681055951 is about 26097.0487028706. The cubic root of 681055951 is about 879.8208790906.

The spelling of 681055951 in words is "six hundred eighty-one million, fifty-five thousand, nine hundred fifty-one".