25137521 has 2 divisors, whose sum is σ = 25137522. Its totient is φ = 25137520.

The previous prime is 25137503. The next prime is 25137523. The reversal of 25137521 is 12573152.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 24850225 + 287296 = 4985^2 + 536^2 .

It is a cyclic number.

It is not a de Polignac number, because 25137521 - 2¹⁰ = 25136497 is a prime.

Together with 25137523, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (25137523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12568760 + 12568761.

It is an arithmetic number, because the mean of its divisors is an integer number (12568761).

Almost surely, 2^25137521 is an apocalyptic number.

It is an amenable number.

25137521 is a deficient number, since it is larger than the sum of its proper divisors (1).

25137521 is an equidigital number, since it uses as much as digits as its factorization.

25137521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2100, while the sum is 26.

The square root of 25137521 is about 5013.7332398124. The cubic root of 25137521 is about 292.9369455108.

The spelling of 25137521 in words is "twenty-five million, one hundred thirty-seven thousand, five hundred twenty-one".