19890874673 has 2 divisors, whose sum is σ = 19890874674. Its totient is φ = 19890874672.

The previous prime is 19890874643. The next prime is 19890874727. The reversal of 19890874673 is 37647809891.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12434034064 + 7456840609 = 111508^2 + 86353^2 .

It is a cyclic number.

It is not a de Polignac number, because 19890874673 - 2⁶ = 19890874609 is a prime.

It is not a weakly prime, because it can be changed into another prime (19890874643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9945437336 + 9945437337.

It is an arithmetic number, because the mean of its divisors is an integer number (9945437337).

Almost surely, 2^19890874673 is an apocalyptic number.

It is an amenable number.

19890874673 is a deficient number, since it is larger than the sum of its proper divisors (1).

19890874673 is an equidigital number, since it uses as much as digits as its factorization.

19890874673 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18289152, while the sum is 62.

The spelling of 19890874673 in words is "nineteen billion, eight hundred ninety million, eight hundred seventy-four thousand, six hundred seventy-three".