25531993 has 2 divisors, whose sum is σ = 25531994. Its totient is φ = 25531992.

The previous prime is 25531973. The next prime is 25531997. The reversal of 25531993 is 39913552.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16064064 + 9467929 = 4008^2 + 3077^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25531993 is a prime.

It is not a weakly prime, because it can be changed into another prime (25531997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12765996 + 12765997.

It is an arithmetic number, because the mean of its divisors is an integer number (12765997).

Almost surely, 2^25531993 is an apocalyptic number.

It is an amenable number.

25531993 is a deficient number, since it is larger than the sum of its proper divisors (1).

25531993 is an equidigital number, since it uses as much as digits as its factorization.

25531993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 36450, while the sum is 37.

The square root of 25531993 is about 5052.9192552425. The cubic root of 25531993 is about 294.4613093566.

The spelling of 25531993 in words is "twenty-five million, five hundred thirty-one thousand, nine hundred ninety-three".