25123621 has 2 divisors, whose sum is σ = 25123622. Its totient is φ = 25123620.

The previous prime is 25123619. The next prime is 25123639. The reversal of 25123621 is 12632152.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17892900 + 7230721 = 4230^2 + 2689^2 .

It is a cyclic number.

It is not a de Polignac number, because 25123621 - 2¹ = 25123619 is a prime.

Together with 25123619, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 25123592 and 25123601.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25123661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12561810 + 12561811.

It is an arithmetic number, because the mean of its divisors is an integer number (12561811).

Almost surely, 2^25123621 is an apocalyptic number.

It is an amenable number.

25123621 is a deficient number, since it is larger than the sum of its proper divisors (1).

25123621 is an equidigital number, since it uses as much as digits as its factorization.

25123621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 720, while the sum is 22.

The square root of 25123621 is about 5012.3468555159. The cubic root of 25123621 is about 292.8829415872.

Adding to 25123621 its reverse (12632152), we get a palindrome (37755773).

The spelling of 25123621 in words is "twenty-five million, one hundred twenty-three thousand, six hundred twenty-one".