20731425 has 48 divisors (see below), whose sum is σ = 40289088. Its totient is φ = 9273600.

The previous prime is 20731423. The next prime is 20731429. The reversal of 20731425 is 52413702.

It is not a de Polignac number, because 20731425 - 2¹ = 20731423 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 20731395 and 20731404.

It is not an unprimeable number, because it can be changed into a prime (20731423) 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 47 ways as a sum of consecutive naturals, for example, 9759 + ... + 11691.

It is an arithmetic number, because the mean of its divisors is an integer number (839356).

Almost surely, 2^20731425 is an apocalyptic number.

20731425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20731425 is a deficient number, since it is larger than the sum of its proper divisors (19557663).

20731425 is a wasteful number, since it uses less digits than its factorization.

20731425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1970 (or 1965 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 24.

The square root of 20731425 is about 4553.1774619490. The cubic root of 20731425 is about 274.7112119903.

It can be divided in two parts, 20 and 731425, that added together give a triangular number (731445 = T₁₂₀₉).

The spelling of 20731425 in words is "twenty million, seven hundred thirty-one thousand, four hundred twenty-five".