25499021 has 2 divisors, whose sum is σ = 25499022. Its totient is φ = 25499020.

The previous prime is 25499003. The next prime is 25499027. The reversal of 25499021 is 12099452.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16564900 + 8934121 = 4070^2 + 2989^2 .

It is a cyclic number.

It is not a de Polignac number, because 25499021 - 2¹⁴ = 25482637 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25499027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12749510 + 12749511.

It is an arithmetic number, because the mean of its divisors is an integer number (12749511).

Almost surely, 2^25499021 is an apocalyptic number.

It is an amenable number.

25499021 is a deficient number, since it is larger than the sum of its proper divisors (1).

25499021 is an equidigital number, since it uses as much as digits as its factorization.

25499021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6480, while the sum is 32.

The square root of 25499021 is about 5049.6555328062. The cubic root of 25499021 is about 294.3344990357.

The spelling of 25499021 in words is "twenty-five million, four hundred ninety-nine thousand, twenty-one".