20397825 has 60 divisors (see below), whose sum is σ = 43211520. Its totient is φ = 9318240.

The previous prime is 20397823. The next prime is 20397827. The reversal of 20397825 is 52879302.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (20397823) and next prime (20397827).

It is not a de Polignac number, because 20397825 - 2¹ = 20397823 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20397825.

It is not an unprimeable number, because it can be changed into a prime (20397823) 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 59 ways as a sum of consecutive naturals, for example, 13456 + ... + 14894.

It is an arithmetic number, because the mean of its divisors is an integer number (720192).

Almost surely, 2^20397825 is an apocalyptic number.

20397825 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20397825 is an abundant number, since it is smaller than the sum of its proper divisors (22813695).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20397825 is a wasteful number, since it uses less digits than its factorization.

20397825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1468 (or 1454 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The square root of 20397825 is about 4516.3951332894. The cubic root of 20397825 is about 273.2297305489.

The spelling of 20397825 in words is "twenty million, three hundred ninety-seven thousand, eight hundred twenty-five".