16925621 has 4 divisors (see below), whose sum is σ = 16971372. Its totient is φ = 16879872.

The previous prime is 16925611. The next prime is 16925633. The reversal of 16925621 is 12652961.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12652961 = 29 ⋅436309.

It can be written as a sum of positive squares in 2 ways, for example, as 9302500 + 7623121 = 3050^2 + 2761^2 .

It is a cyclic number.

It is not a de Polignac number, because 16925621 - 2¹⁰ = 16924597 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 (16925611) 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, 22316 + ... + 23061.

It is an arithmetic number, because the mean of its divisors is an integer number (4242843).

Almost surely, 2^16925621 is an apocalyptic number.

It is an amenable number.

16925621 is a deficient number, since it is larger than the sum of its proper divisors (45751).

16925621 is an equidigital number, since it uses as much as digits as its factorization.

16925621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45750.

The product of its digits is 6480, while the sum is 32.

The square root of 16925621 is about 4114.0759594349. The cubic root of 16925621 is about 256.7526120978.

The spelling of 16925621 in words is "sixteen million, nine hundred twenty-five thousand, six hundred twenty-one".