19905725 has 24 divisors (see below), whose sum is σ = 29873088. Its totient is φ = 12844800.

The previous prime is 19905719. The next prime is 19905727. The reversal of 19905725 is 52750991.

It is not a de Polignac number, because 19905725 - 2²⁰ = 18857149 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19905727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 371 + ... + 6320.

It is an arithmetic number, because the mean of its divisors is an integer number (1244712).

Almost surely, 2^19905725 is an apocalyptic number.

It is an amenable number.

19905725 is a deficient number, since it is larger than the sum of its proper divisors (9967363).

19905725 is a wasteful number, since it uses less digits than its factorization.

19905725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6725 (or 6720 counting only the distinct ones).

The product of its (nonzero) digits is 28350, while the sum is 38.

The square root of 19905725 is about 4461.5832391652. The cubic root of 19905725 is about 271.0145868884.

The spelling of 19905725 in words is "nineteen million, nine hundred five thousand, seven hundred twenty-five".