20681025 has 48 divisors (see below), whose sum is σ = 37616640. Its totient is φ = 9979200.

The previous prime is 20681021. The next prime is 20681029. The reversal of 20681025 is 52018602.

It is an interprime number because it is at equal distance from previous prime (20681021) and next prime (20681029).

It is not a de Polignac number, because 20681025 - 2² = 20681021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20680986 and 20681004.

It is not an unprimeable number, because it can be changed into a prime (20681021) 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, 32460 + ... + 33090.

It is an arithmetic number, because the mean of its divisors is an integer number (783680).

Almost surely, 2^20681025 is an apocalyptic number.

20681025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20681025 is a deficient number, since it is larger than the sum of its proper divisors (16935615).

20681025 is a wasteful number, since it uses less digits than its factorization.

20681025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 686 (or 681 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 24.

The square root of 20681025 is about 4547.6394975855. The cubic root of 20681025 is about 274.4884152761.

Adding to 20681025 its reverse (52018602), we get a palindrome (72699627).

The spelling of 20681025 in words is "twenty million, six hundred eighty-one thousand, twenty-five".