25213621 has 2 divisors, whose sum is σ = 25213622. Its totient is φ = 25213620.

The previous prime is 25213607. The next prime is 25213649. The reversal of 25213621 is 12631252.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20151121 + 5062500 = 4489^2 + 2250^2 .

It is a cyclic number.

It is not a de Polignac number, because 25213621 - 2⁹ = 25213109 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 25213592 and 25213601.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25213651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12606810 + 12606811.

It is an arithmetic number, because the mean of its divisors is an integer number (12606811).

Almost surely, 2^25213621 is an apocalyptic number.

It is an amenable number.

25213621 is a deficient number, since it is larger than the sum of its proper divisors (1).

25213621 is an equidigital number, since it uses as much as digits as its factorization.

25213621 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 25213621 is about 5021.3166600006. The cubic root of 25213621 is about 293.2322549753.

Adding to 25213621 its reverse (12631252), we get a palindrome (37844873).

The spelling of 25213621 in words is "twenty-five million, two hundred thirteen thousand, six hundred twenty-one".