19694665740397 has 2 divisors, whose sum is σ = 19694665740398. Its totient is φ = 19694665740396.

The previous prime is 19694665740391. The next prime is 19694665740401. The reversal of 19694665740397 is 79304756649691.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14218827057796 + 5475838682601 = 3770786^2 + 2340051^2 .

It is a cyclic number.

It is not a de Polignac number, because 19694665740397 - 2²⁷ = 19694531522669 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19694665740391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9847332870198 + 9847332870199.

It is an arithmetic number, because the mean of its divisors is an integer number (9847332870199).

Almost surely, 2^{19694665740397} is an apocalyptic number.

It is an amenable number.

19694665740397 is a deficient number, since it is larger than the sum of its proper divisors (1).

19694665740397 is an equidigital number, since it uses as much as digits as its factorization.

19694665740397 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1851776640, while the sum is 76.

The spelling of 19694665740397 in words is "nineteen trillion, six hundred ninety-four billion, six hundred sixty-five million, seven hundred forty thousand, three hundred ninety-seven".