16421825 has 24 divisors (see below), whose sum is σ = 23516352. Its totient is φ = 11142720.

The previous prime is 16421807. The next prime is 16421827. The reversal of 16421825 is 52812461.

It is not a de Polignac number, because 16421825 - 2²² = 12227521 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (16421827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 18287 + ... + 19163.

It is an arithmetic number, because the mean of its divisors is an integer number (979848).

Almost surely, 2^16421825 is an apocalyptic number.

It is an amenable number.

16421825 is a deficient number, since it is larger than the sum of its proper divisors (7094527).

16421825 is a wasteful number, since it uses less digits than its factorization.

16421825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1001 (or 996 counting only the distinct ones).

The product of its digits is 3840, while the sum is 29.

The square root of 16421825 is about 4052.3851001602. The cubic root of 16421825 is about 254.1794720175.

The spelling of 16421825 in words is "sixteen million, four hundred twenty-one thousand, eight hundred twenty-five".