26986991 has 2 divisors, whose sum is σ = 26986992. Its totient is φ = 26986990.

The previous prime is 26986969. The next prime is 26987021. The reversal of 26986991 is 19968962.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-26986991 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26986901) 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, 13493495 + 13493496.

It is an arithmetic number, because the mean of its divisors is an integer number (13493496).

Almost surely, 2^26986991 is an apocalyptic number.

26986991 is a deficient number, since it is larger than the sum of its proper divisors (1).

26986991 is an equidigital number, since it uses as much as digits as its factorization.

26986991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 419904, while the sum is 50.

The square root of 26986991 is about 5194.9004802787. The cubic root of 26986991 is about 299.9518107783.

The spelling of 26986991 in words is "twenty-six million, nine hundred eighty-six thousand, nine hundred ninety-one".