16399738 has 4 divisors (see below), whose sum is σ = 24599610. Its totient is φ = 8199868.

The previous prime is 16399729. The next prime is 16399739. The reversal of 16399738 is 83799361.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 10673289 + 5726449 = 3267^2 + 2393^2 .

It is not an unprimeable number, because it can be changed into a prime (16399739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4099933 + ... + 4099936.

Almost surely, 2^16399738 is an apocalyptic number.

16399738 is a deficient number, since it is larger than the sum of its proper divisors (8199872).

16399738 is an equidigital number, since it uses as much as digits as its factorization.

16399738 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8199871.

The product of its digits is 244944, while the sum is 46.

The square root of 16399738 is about 4049.6589979898. The cubic root of 16399738 is about 254.0654655898.

The spelling of 16399738 in words is "sixteen million, three hundred ninety-nine thousand, seven hundred thirty-eight".