25539973 has 2 divisors, whose sum is σ = 25539974. Its totient is φ = 25539972.

The previous prime is 25539949. The next prime is 25539991. The reversal of 25539973 is 37993552.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 22724289 + 2815684 = 4767^2 + 1678^2 .

It is a cyclic number.

It is not a de Polignac number, because 25539973 - 2²¹ = 23442821 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25539473) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12769986 + 12769987.

It is an arithmetic number, because the mean of its divisors is an integer number (12769987).

Almost surely, 2^25539973 is an apocalyptic number.

It is an amenable number.

25539973 is a deficient number, since it is larger than the sum of its proper divisors (1).

25539973 is an equidigital number, since it uses as much as digits as its factorization.

25539973 is an evil number, because the sum of its binary digits is even.

The product of its digits is 255150, while the sum is 43.

The square root of 25539973 is about 5053.7088360926. The cubic root of 25539973 is about 294.4919840280.

The spelling of 25539973 in words is "twenty-five million, five hundred thirty-nine thousand, nine hundred seventy-three".