26249981 has 2 divisors, whose sum is σ = 26249982. Its totient is φ = 26249980.

The previous prime is 26249957. The next prime is 26249987. The reversal of 26249981 is 18994262.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17926756 + 8323225 = 4234^2 + 2885^2 .

It is a cyclic number.

It is not a de Polignac number, because 26249981 - 2⁶ = 26249917 is a prime.

It is a super-2 number, since 2×26249981² = 1378123005000722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26249987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13124990 + 13124991.

It is an arithmetic number, because the mean of its divisors is an integer number (13124991).

Almost surely, 2^26249981 is an apocalyptic number.

It is an amenable number.

26249981 is a deficient number, since it is larger than the sum of its proper divisors (1).

26249981 is an equidigital number, since it uses as much as digits as its factorization.

26249981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 62208, while the sum is 41.

The square root of 26249981 is about 5123.4735287693. The cubic root of 26249981 is about 297.1960259337.

The spelling of 26249981 in words is "twenty-six million, two hundred forty-nine thousand, nine hundred eighty-one".