19694665740401 has 2 divisors, whose sum is σ = 19694665740402. Its totient is φ = 19694665740400.

The previous prime is 19694665740397. The next prime is 19694665740413. The reversal of 19694665740401 is 10404756649691.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15832560370225 + 3862105370176 = 3979015^2 + 1965224^2 .

It is a cyclic number.

It is not a de Polignac number, because 19694665740401 - 2² = 19694665740397 is a prime.

It is a super-2 number, since 2×19694665740401² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (19694665740461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9847332870200 + 9847332870201.

It is an arithmetic number, because the mean of its divisors is an integer number (9847332870201).

Almost surely, 2^{19694665740401} is an apocalyptic number.

It is an amenable number.

19694665740401 is a deficient number, since it is larger than the sum of its proper divisors (1).

19694665740401 is an equidigital number, since it uses as much as digits as its factorization.

19694665740401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 39191040, while the sum is 62.

The spelling of 19694665740401 in words is "nineteen trillion, six hundred ninety-four billion, six hundred sixty-five million, seven hundred forty thousand, four hundred one".