16390042 has 4 divisors (see below), whose sum is σ = 24585066. Its totient is φ = 8195020.

The previous prime is 16390039. The next prime is 16390043. The reversal of 16390042 is 24009361.

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., 14676561 + 1713481 = 3831^2 + 1309^2 .

It is a junction number, because it is equal to n+sod(n) for n = 16389989 and 16390016.

It is not an unprimeable number, because it can be changed into a prime (16390043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4097509 + ... + 4097512.

Almost surely, 2^16390042 is an apocalyptic number.

16390042 is a deficient number, since it is larger than the sum of its proper divisors (8195024).

16390042 is an equidigital number, since it uses as much as digits as its factorization.

16390042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8195023.

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 16390042 is about 4048.4616831582. The cubic root of 16390042 is about 254.0153854322.

The spelling of 16390042 in words is "sixteen million, three hundred ninety thousand, forty-two".