25921387 has 2 divisors, whose sum is σ = 25921388. Its totient is φ = 25921386.

The previous prime is 25921369. The next prime is 25921397. The reversal of 25921387 is 78312952.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25921387 is a prime.

It is not a weakly prime, because it can be changed into another prime (25921327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12960693 + 12960694.

It is an arithmetic number, because the mean of its divisors is an integer number (12960694).

Almost surely, 2^25921387 is an apocalyptic number.

25921387 is a deficient number, since it is larger than the sum of its proper divisors (1).

25921387 is an equidigital number, since it uses as much as digits as its factorization.

25921387 is an evil number, because the sum of its binary digits is even.

The product of its digits is 30240, while the sum is 37.

The square root of 25921387 is about 5091.3050389856. The cubic root of 25921387 is about 295.9507275850.

The spelling of 25921387 in words is "twenty-five million, nine hundred twenty-one thousand, three hundred eighty-seven".