16399378 has 4 divisors (see below), whose sum is σ = 24599070. Its totient is φ = 8199688.

The previous prime is 16399363. The next prime is 16399393. The reversal of 16399378 is 87399361.

16399378 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is an interprime number because it is at equal distance from previous prime (16399363) and next prime (16399393).

It can be written as a sum of positive squares in only one way, i.e., 14768649 + 1630729 = 3843^2 + 1277^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4099843 + ... + 4099846.

Almost surely, 2^16399378 is an apocalyptic number.

16399378 is a deficient number, since it is larger than the sum of its proper divisors (8199692).

16399378 is an equidigital number, since it uses as much as digits as its factorization.

16399378 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8199691.

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

The square root of 16399378 is about 4049.6145495590. The cubic root of 16399378 is about 254.0636065309.

The spelling of 16399378 in words is "sixteen million, three hundred ninety-nine thousand, three hundred seventy-eight".