16128989 has 2 divisors, whose sum is σ = 16128990. Its totient is φ = 16128988.

The previous prime is 16128961. The next prime is 16129067. The reversal of 16128989 is 98982161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15288100 + 840889 = 3910^2 + 917^2 .

It is a cyclic number.

It is not a de Polignac number, because 16128989 - 2¹² = 16124893 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16128389) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8064494 + 8064495.

It is an arithmetic number, because the mean of its divisors is an integer number (8064495).

Almost surely, 2^16128989 is an apocalyptic number.

It is an amenable number.

16128989 is a deficient number, since it is larger than the sum of its proper divisors (1).

16128989 is an equidigital number, since it uses as much as digits as its factorization.

16128989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 62208, while the sum is 44.

The square root of 16128989 is about 4016.0912589233. The cubic root of 16128989 is about 252.6595482184.

It can be divided in two parts, 1612 and 8989, that added together give a palindrome (10601).

The spelling of 16128989 in words is "sixteen million, one hundred twenty-eight thousand, nine hundred eighty-nine".