19701193681 has 16 divisors (see below), whose sum is σ = 21319207504. Its totient is φ = 18098049024.

The previous prime is 19701193669. The next prime is 19701193709. The reversal of 19701193681 is 18639110791.

It can be written as a sum of positive squares in 8 ways, for example, as 613008081 + 19088185600 = 24759^2 + 138160^2 .

It is a cyclic number.

It is not a de Polignac number, because 19701193681 - 2⁷ = 19701193553 is a prime.

It is a super-2 number, since 2×19701193681² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19701193381) 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, 2354401 + ... + 2362753.

It is an arithmetic number, because the mean of its divisors is an integer number (1332450469).

Almost surely, 2^19701193681 is an apocalyptic number.

It is an amenable number.

19701193681 is a deficient number, since it is larger than the sum of its proper divisors (1618013823).

19701193681 is a wasteful number, since it uses less digits than its factorization.

19701193681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9220.

The product of its (nonzero) digits is 81648, while the sum is 46.

The spelling of 19701193681 in words is "nineteen billion, seven hundred one million, one hundred ninety-three thousand, six hundred eighty-one".