681940166616 has 64 divisors (see below), whose sum is σ = 2005706383200. Its totient is φ = 213942011904.

The previous prime is 681940166561. The next prime is 681940166617. The reversal of 681940166616 is 616661049186.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681940166617) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 92853105 + ... + 92860448.

Almost surely, 2^681940166616 is an apocalyptic number.

It is an amenable number.

681940166616 is an abundant number, since it is smaller than the sum of its proper divisors (1323766216584).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

681940166616 is a wasteful number, since it uses less digits than its factorization.

681940166616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185713585 (or 185713575 counting only the distinct ones).

The product of its (nonzero) digits is 2239488, while the sum is 54.

The spelling of 681940166616 in words is "six hundred eighty-one billion, nine hundred forty million, one hundred sixty-six thousand, six hundred sixteen".