16398989 has 2 divisors, whose sum is σ = 16398990. Its totient is φ = 16398988.

The previous prime is 16398983. The next prime is 16399003. The reversal of 16398989 is 98989361.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10956100 + 5442889 = 3310^2 + 2333^2 .

It is an emirp because it is prime and its reverse (98989361) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16398989 - 2¹² = 16394893 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 16398989.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16398983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8199494 + 8199495.

It is an arithmetic number, because the mean of its divisors is an integer number (8199495).

Almost surely, 2^16398989 is an apocalyptic number.

It is an amenable number.

16398989 is a deficient number, since it is larger than the sum of its proper divisors (1).

16398989 is an equidigital number, since it uses as much as digits as its factorization.

16398989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 839808, while the sum is 53.

The square root of 16398989 is about 4049.5665200117. The cubic root of 16398989 is about 254.0615976839.

The spelling of 16398989 in words is "sixteen million, three hundred ninety-eight thousand, nine hundred eighty-nine".