26991853 has 4 divisors (see below), whose sum is σ = 30847840. Its totient is φ = 23135868.

The previous prime is 26991827. The next prime is 26991859. The reversal of 26991853 is 35819962.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a de Polignac number, because none of the positive numbers 2^k-26991853 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (26991859) 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 in 3 ways as a sum of consecutive naturals, for example, 1927983 + ... + 1927996.

It is an arithmetic number, because the mean of its divisors is an integer number (7711960).

Almost surely, 2^26991853 is an apocalyptic number.

It is an amenable number.

26991853 is a deficient number, since it is larger than the sum of its proper divisors (3855987).

26991853 is an equidigital number, since it uses as much as digits as its factorization.

26991853 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3855986.

The product of its digits is 116640, while the sum is 43.

The square root of 26991853 is about 5195.3684181201. The cubic root of 26991853 is about 299.9698228905.

The spelling of 26991853 in words is "twenty-six million, nine hundred ninety-one thousand, eight hundred fifty-three".