16221807 has 12 divisors (see below), whose sum is σ = 26778960. Its totient is φ = 9269568.

The previous prime is 16221761. The next prime is 16221823. The reversal of 16221807 is 70812261.

It is not a de Polignac number, because 16221807 - 2⁶ = 16221743 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16221827) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 128682 + ... + 128807.

It is an arithmetic number, because the mean of its divisors is an integer number (2231580).

Almost surely, 2^16221807 is an apocalyptic number.

16221807 is a deficient number, since it is larger than the sum of its proper divisors (10557153).

16221807 is a wasteful number, since it uses less digits than its factorization.

16221807 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 257502 (or 257499 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 27.

The square root of 16221807 is about 4027.6304448149. The cubic root of 16221807 is about 253.1432840931.

The spelling of 16221807 in words is "sixteen million, two hundred twenty-one thousand, eight hundred seven".