16402391 has 2 divisors, whose sum is σ = 16402392. Its totient is φ = 16402390.

The previous prime is 16402369. The next prime is 16402403. The reversal of 16402391 is 19320461.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 16402391 - 2¹⁸ = 16140247 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 16402391.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16401391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8201195 + 8201196.

It is an arithmetic number, because the mean of its divisors is an integer number (8201196).

Almost surely, 2^16402391 is an apocalyptic number.

16402391 is a deficient number, since it is larger than the sum of its proper divisors (1).

16402391 is an equidigital number, since it uses as much as digits as its factorization.

16402391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 26.

The square root of 16402391 is about 4049.9865431875. The cubic root of 16402391 is about 254.0791649822.

The spelling of 16402391 in words is "sixteen million, four hundred two thousand, three hundred ninety-one".