16902021 has 4 divisors (see below), whose sum is σ = 22536032. Its totient is φ = 11268012.

The previous prime is 16901981. The next prime is 16902031. The reversal of 16902021 is 12020961.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 16902021 - 2⁶ = 16901957 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16902031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2817001 + ... + 2817006.

It is an arithmetic number, because the mean of its divisors is an integer number (5634008).

Almost surely, 2^16902021 is an apocalyptic number.

It is an amenable number.

16902021 is a deficient number, since it is larger than the sum of its proper divisors (5634011).

16902021 is an equidigital number, since it uses as much as digits as its factorization.

16902021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5634010.

The product of its (nonzero) digits is 216, while the sum is 21.

The square root of 16902021 is about 4111.2067571456. The cubic root of 16902021 is about 256.6332234682.

Adding to 16902021 its reverse (12020961), we get a palindrome (28922982).

The spelling of 16902021 in words is "sixteen million, nine hundred two thousand, twenty-one".