681562520961 has 32 divisors (see below), whose sum is σ = 1067857862400. Its totient is φ = 378552529920.

The previous prime is 681562520911. The next prime is 681562521011. The reversal of 681562520961 is 169025265186.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (681562520911) and next prime (681562521011).

It is not a de Polignac number, because 681562520961 - 2¹¹ = 681562518913 is a prime.

It is not an unprimeable number, because it can be changed into a prime (681562520911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1239756 + ... + 1702973.

It is an arithmetic number, because the mean of its divisors is an integer number (33370558200).

Almost surely, 2^681562520961 is an apocalyptic number.

It is an amenable number.

681562520961 is a deficient number, since it is larger than the sum of its proper divisors (386295341439).

681562520961 is a wasteful number, since it uses less digits than its factorization.

681562520961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2943049.

The product of its (nonzero) digits is 1555200, while the sum is 51.

The spelling of 681562520961 in words is "six hundred eighty-one billion, five hundred sixty-two million, five hundred twenty thousand, nine hundred sixty-one".