20808025 has 12 divisors (see below), whose sum is σ = 29488192. Its totient is φ = 14268240.

The previous prime is 20808019. The next prime is 20808071. The reversal of 20808025 is 52080802.

It is not a de Polignac number, because 20808025 - 2²¹ = 18710873 is a prime.

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

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 59277 + ... + 59626.

Almost surely, 2^20808025 is an apocalyptic number.

20808025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20808025 is a deficient number, since it is larger than the sum of its proper divisors (8680167).

20808025 is a wasteful number, since it uses less digits than its factorization.

20808025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118920 (or 118915 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 25.

The square root of 20808025 is about 4561.5814143781. The cubic root of 20808025 is about 275.0491372251.

Adding to 20808025 its reverse (52080802), we get a palindrome (72888827).

The spelling of 20808025 in words is "twenty million, eight hundred eight thousand, twenty-five".