20705425 has 12 divisors (see below), whose sum is σ = 27650140. Its totient is φ = 15289920.

The previous prime is 20705423. The next prime is 20705453. The reversal of 20705425 is 52450702.

It can be written as a sum of positive squares in 6 ways, for example, as 6235009 + 14470416 = 2497^2 + 3804^2 .

It is not a de Polignac number, because 20705425 - 2¹ = 20705423 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a self number, because there is not a number n which added to its sum of digits gives 20705425.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20705423) 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 11 ways as a sum of consecutive naturals, for example, 31530 + ... + 32179.

Almost surely, 2^20705425 is an apocalyptic number.

20705425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20705425 is a deficient number, since it is larger than the sum of its proper divisors (6944715).

20705425 is a wasteful number, since it uses less digits than its factorization.

20705425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63732 (or 63727 counting only the distinct ones).

The product of its (nonzero) digits is 2800, while the sum is 25.

The square root of 20705425 is about 4550.3214172188. The cubic root of 20705425 is about 274.5963223244.

The spelling of 20705425 in words is "twenty million, seven hundred five thousand, four hundred twenty-five".