19935989 has 2 divisors, whose sum is σ = 19935990. Its totient is φ = 19935988.

The previous prime is 19935983. The next prime is 19936031. The reversal of 19935989 is 98953991.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14691889 + 5244100 = 3833^2 + 2290^2 .

It is a cyclic number.

It is not a de Polignac number, because 19935989 - 2¹⁶ = 19870453 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19935989.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19935983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9967994 + 9967995.

It is an arithmetic number, because the mean of its divisors is an integer number (9967995).

Almost surely, 2^19935989 is an apocalyptic number.

It is an amenable number.

19935989 is a deficient number, since it is larger than the sum of its proper divisors (1).

19935989 is an equidigital number, since it uses as much as digits as its factorization.

19935989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 787320, while the sum is 53.

The square root of 19935989 is about 4464.9735721502. The cubic root of 19935989 is about 271.1518645190.

The spelling of 19935989 in words is "nineteen million, nine hundred thirty-five thousand, nine hundred eighty-nine".