20025621 has 72 divisors (see below), whose sum is σ = 37844352. Its totient is φ = 9979200.

The previous prime is 20025613. The next prime is 20025637. The reversal of 20025621 is 12652002.

20025621 is a `hidden beast` number, since 20 + 0 + 25 + 621 = 666.

It is not a de Polignac number, because 20025621 - 2³ = 20025613 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20025594 and 20025603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20025611) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 282016 + ... + 282086.

It is an arithmetic number, because the mean of its divisors is an integer number (525616).

Almost surely, 2^20025621 is an apocalyptic number.

20025621 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20025621 is a deficient number, since it is larger than the sum of its proper divisors (17818731).

20025621 is a wasteful number, since it uses less digits than its factorization.

20025621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143 (or 129 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 20025621 is about 4474.9995530726. Note that the first 3 decimals coincide. The cubic root of 20025621 is about 271.5576223554.

Adding to 20025621 its reverse (12652002), we get a palindrome (32677623).

The spelling of 20025621 in words is "twenty million, twenty-five thousand, six hundred twenty-one".