16921725 has 24 divisors (see below), whose sum is σ = 28664832. Its totient is φ = 8803200.

The previous prime is 16921699. The next prime is 16921727. The reversal of 16921725 is 52712961.

It is not a de Polignac number, because 16921725 - 2¹¹ = 16919677 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16921727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 324 + ... + 5826.

It is an arithmetic number, because the mean of its divisors is an integer number (1194368).

Almost surely, 2^16921725 is an apocalyptic number.

16921725 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

16921725 is a deficient number, since it is larger than the sum of its proper divisors (11743107).

16921725 is a wasteful number, since it uses less digits than its factorization.

16921725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5557 (or 5552 counting only the distinct ones).

The product of its digits is 7560, while the sum is 33.

The square root of 16921725 is about 4113.6024358219. The cubic root of 16921725 is about 256.7329105078.

The spelling of 16921725 in words is "sixteen million, nine hundred twenty-one thousand, seven hundred twenty-five".