16421803 has 4 divisors (see below), whose sum is σ = 16653168. Its totient is φ = 16190440.

The previous prime is 16421777. The next prime is 16421807. The reversal of 16421803 is 30812461.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 30812461 = 521 ⋅59141.

It is a cyclic number.

It is not a de Polignac number, because 16421803 - 2¹⁷ = 16290731 is a prime.

It is a super-2 number, since 2×16421803² = 539351227541618, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16421807) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 115576 + ... + 115717.

It is an arithmetic number, because the mean of its divisors is an integer number (4163292).

Almost surely, 2^16421803 is an apocalyptic number.

16421803 is a deficient number, since it is larger than the sum of its proper divisors (231365).

16421803 is an equidigital number, since it uses as much as digits as its factorization.

16421803 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 231364.

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 16421803 is about 4052.3823857084. The cubic root of 16421803 is about 254.1793585110.

The spelling of 16421803 in words is "sixteen million, four hundred twenty-one thousand, eight hundred three".