20431725 has 12 divisors (see below), whose sum is σ = 33780576. Its totient is φ = 10896880.

The previous prime is 20431721. The next prime is 20431729. The reversal of 20431725 is 52713402.

It is an interprime number because it is at equal distance from previous prime (20431721) and next prime (20431729).

It is not a de Polignac number, because 20431725 - 2² = 20431721 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 20431695 and 20431704.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20431721) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 136137 + ... + 136286.

It is an arithmetic number, because the mean of its divisors is an integer number (2815048).

Almost surely, 2^20431725 is an apocalyptic number.

20431725 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20431725 is a deficient number, since it is larger than the sum of its proper divisors (13348851).

20431725 is a wasteful number, since it uses less digits than its factorization.

20431725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 272436 (or 272431 counting only the distinct ones).

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

The square root of 20431725 is about 4520.1465684201. The cubic root of 20431725 is about 273.3810107525.

The spelling of 20431725 in words is "twenty million, four hundred thirty-one thousand, seven hundred twenty-five".