20305425 has 24 divisors (see below), whose sum is σ = 38368576. Its totient is φ = 9282240.

The previous prime is 20305421. The next prime is 20305427. The reversal of 20305425 is 52450302.

It is not a de Polignac number, because 20305425 - 2² = 20305421 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20305421) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 18814 + ... + 19863.

Almost surely, 2^20305425 is an apocalyptic number.

20305425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20305425 is a deficient number, since it is larger than the sum of its proper divisors (18063151).

20305425 is a wasteful number, since it uses less digits than its factorization.

20305425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38697 (or 38692 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 21.

The square root of 20305425 is about 4506.1541251937. The cubic root of 20305425 is about 272.8165387086.

Adding to 20305425 its reverse (52450302), we get a palindrome (72755727).

The spelling of 20305425 in words is "twenty million, three hundred five thousand, four hundred twenty-five".