25127821 has 2 divisors, whose sum is σ = 25127822. Its totient is φ = 25127820.

The previous prime is 25127813. The next prime is 25127857. The reversal of 25127821 is 12872152.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 23474025 + 1653796 = 4845^2 + 1286^2 .

It is a cyclic number.

It is not a de Polignac number, because 25127821 - 2³ = 25127813 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 25127821.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25127621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12563910 + 12563911.

It is an arithmetic number, because the mean of its divisors is an integer number (12563911).

Almost surely, 2^25127821 is an apocalyptic number.

It is an amenable number.

25127821 is a deficient number, since it is larger than the sum of its proper divisors (1).

25127821 is an equidigital number, since it uses as much as digits as its factorization.

25127821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2240, while the sum is 28.

The square root of 25127821 is about 5012.7658034263. The cubic root of 25127821 is about 292.8992614191.

Adding to 25127821 its reverse (12872152), we get a palindrome (37999973).

The spelling of 25127821 in words is "twenty-five million, one hundred twenty-seven thousand, eight hundred twenty-one".