681411981 has 8 divisors (see below), whose sum is σ = 911509984. Its totient is φ = 452794320.

The previous prime is 681411979. The next prime is 681412001. The reversal of 681411981 is 189114186.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 681411981 - 2¹ = 681411979 is a prime.

It is a super-2 number, since 2×681411981² = 928644575700688722, 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 (681411971) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 369010 + ... + 370851.

It is an arithmetic number, because the mean of its divisors is an integer number (113938748).

Almost surely, 2^681411981 is an apocalyptic number.

It is an amenable number.

681411981 is a deficient number, since it is larger than the sum of its proper divisors (230098003).

681411981 is a wasteful number, since it uses less digits than its factorization.

681411981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 740171.

The product of its digits is 13824, while the sum is 39.

The square root of 681411981 is about 26103.8690810385. The cubic root of 681411981 is about 879.9741646169.

The spelling of 681411981 in words is "six hundred eighty-one million, four hundred eleven thousand, nine hundred eighty-one".