25673821 has 2 divisors, whose sum is σ = 25673822. Its totient is φ = 25673820.

The previous prime is 25673789. The next prime is 25673861. The reversal of 25673821 is 12837652.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 23145721 + 2528100 = 4811^2 + 1590^2 .

It is a cyclic number.

It is not a de Polignac number, because 25673821 - 2⁵ = 25673789 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25673861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12836910 + 12836911.

It is an arithmetic number, because the mean of its divisors is an integer number (12836911).

Almost surely, 2^25673821 is an apocalyptic number.

It is an amenable number.

25673821 is a deficient number, since it is larger than the sum of its proper divisors (1).

25673821 is an equidigital number, since it uses as much as digits as its factorization.

25673821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20160, while the sum is 34.

The square root of 25673821 is about 5066.9340828552. The cubic root of 25673821 is about 295.0055385343.

The spelling of 25673821 in words is "twenty-five million, six hundred seventy-three thousand, eight hundred twenty-one".