16021399 has 2 divisors, whose sum is σ = 16021400. Its totient is φ = 16021398.

The previous prime is 16021387. The next prime is 16021417. The reversal of 16021399 is 99312061.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 16021399 - 2⁵ = 16021367 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 16021399.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16021339) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8010699 + 8010700.

It is an arithmetic number, because the mean of its divisors is an integer number (8010700).

Almost surely, 2^16021399 is an apocalyptic number.

16021399 is a deficient number, since it is larger than the sum of its proper divisors (1).

16021399 is an equidigital number, since it uses as much as digits as its factorization.

16021399 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2916, while the sum is 31.

The square root of 16021399 is about 4002.6739812280. The cubic root of 16021399 is about 252.0964976452.

The spelling of 16021399 in words is "sixteen million, twenty-one thousand, three hundred ninety-nine".