26197421 has 2 divisors, whose sum is σ = 26197422. Its totient is φ = 26197420.

The previous prime is 26197403. The next prime is 26197441. The reversal of 26197421 is 12479162.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24900100 + 1297321 = 4990^2 + 1139^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-26197421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26197441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13098710 + 13098711.

It is an arithmetic number, because the mean of its divisors is an integer number (13098711).

Almost surely, 2^26197421 is an apocalyptic number.

It is an amenable number.

26197421 is a deficient number, since it is larger than the sum of its proper divisors (1).

26197421 is an equidigital number, since it uses as much as digits as its factorization.

26197421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6048, while the sum is 32.

The square root of 26197421 is about 5118.3416259566. The cubic root of 26197421 is about 296.9975361342.

The spelling of 26197421 in words is "twenty-six million, one hundred ninety-seven thousand, four hundred twenty-one".