16196821 has 4 divisors (see below), whose sum is σ = 16296352. Its totient is φ = 16097292.

The previous prime is 16196813. The next prime is 16196837. The reversal of 16196821 is 12869161.

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 a cyclic number.

It is not a de Polignac number, because 16196821 - 2³ = 16196813 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 (16196881) 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, 49521 + ... + 49846.

It is an arithmetic number, because the mean of its divisors is an integer number (4074088).

Almost surely, 2^16196821 is an apocalyptic number.

It is an amenable number.

16196821 is a deficient number, since it is larger than the sum of its proper divisors (99531).

16196821 is an equidigital number, since it uses as much as digits as its factorization.

16196821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99530.

The product of its digits is 5184, while the sum is 34.

The square root of 16196821 is about 4024.5274256737. The cubic root of 16196821 is about 253.0132474433.

The spelling of 16196821 in words is "sixteen million, one hundred ninety-six thousand, eight hundred twenty-one".