26537981 has 2 divisors, whose sum is σ = 26537982. Its totient is φ = 26537980.

The previous prime is 26537977. The next prime is 26537983. The reversal of 26537981 is 18973562.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14182756 + 12355225 = 3766^2 + 3515^2 .

It is a cyclic number.

It is not a de Polignac number, because 26537981 - 2² = 26537977 is a prime.

It is a super-2 number, since 2×26537981² = 1408528871112722, which contains 22 as substring.

Together with 26537983, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26537983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13268990 + 13268991.

It is an arithmetic number, because the mean of its divisors is an integer number (13268991).

Almost surely, 2^26537981 is an apocalyptic number.

It is an amenable number.

26537981 is a deficient number, since it is larger than the sum of its proper divisors (1).

26537981 is an equidigital number, since it uses as much as digits as its factorization.

26537981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 90720, while the sum is 41.

The square root of 26537981 is about 5151.5027904486. The cubic root of 26537981 is about 298.2789641844.

The spelling of 26537981 in words is "twenty-six million, five hundred thirty-seven thousand, nine hundred eighty-one".