19740631321 has 2 divisors, whose sum is σ = 19740631322. Its totient is φ = 19740631320.

The previous prime is 19740631303. The next prime is 19740631411. The reversal of 19740631321 is 12313604791.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19722270096 + 18361225 = 140436^2 + 4285^2 .

It is an emirp because it is prime and its reverse (12313604791) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19740631321 - 2⁷ = 19740631193 is a prime.

It is not a weakly prime, because it can be changed into another prime (19740631301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9870315660 + 9870315661.

It is an arithmetic number, because the mean of its divisors is an integer number (9870315661).

Almost surely, 2^19740631321 is an apocalyptic number.

It is an amenable number.

19740631321 is a deficient number, since it is larger than the sum of its proper divisors (1).

19740631321 is an equidigital number, since it uses as much as digits as its factorization.

19740631321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 27216, while the sum is 37.

The spelling of 19740631321 in words is "nineteen billion, seven hundred forty million, six hundred thirty-one thousand, three hundred twenty-one".