16890402409 has 2 divisors, whose sum is σ = 16890402410. Its totient is φ = 16890402408.

The previous prime is 16890402391. The next prime is 16890402443. The reversal of 16890402409 is 90420409861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11049163225 + 5841239184 = 105115^2 + 76428^2 .

It is a cyclic number.

It is not a de Polignac number, because 16890402409 - 2¹¹ = 16890400361 is a prime.

It is not a weakly prime, because it can be changed into another prime (16890402509) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8445201204 + 8445201205.

It is an arithmetic number, because the mean of its divisors is an integer number (8445201205).

Almost surely, 2^16890402409 is an apocalyptic number.

It is an amenable number.

16890402409 is a deficient number, since it is larger than the sum of its proper divisors (1).

16890402409 is an equidigital number, since it uses as much as digits as its factorization.

16890402409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 124416, while the sum is 43.

The spelling of 16890402409 in words is "sixteen billion, eight hundred ninety million, four hundred two thousand, four hundred nine".