16938021 has 8 divisors (see below), whose sum is σ = 22613920. Its totient is φ = 11277072.

The previous prime is 16938013. The next prime is 16938023. The reversal of 16938021 is 12083961.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 16938021 - 2³ = 16938013 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 16938021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16938023) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 751 + ... + 5868.

It is an arithmetic number, because the mean of its divisors is an integer number (2826740).

Almost surely, 2^16938021 is an apocalyptic number.

It is an amenable number.

16938021 is a deficient number, since it is larger than the sum of its proper divisors (5675899).

16938021 is an equidigital number, since it uses as much as digits as its factorization.

16938021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7475.

The product of its (nonzero) digits is 2592, while the sum is 30.

The square root of 16938021 is about 4115.5827047941. The cubic root of 16938021 is about 256.8152972468.

The spelling of 16938021 in words is "sixteen million, nine hundred thirty-eight thousand, twenty-one".