26991951 has 32 divisors (see below), whose sum is σ = 44044800. Its totient is φ = 14359680.

The previous prime is 26991941. The next prime is 26991967. The reversal of 26991951 is 15919962.

It is a happy number.

It is not a de Polignac number, because 26991951 - 2⁵ = 26991919 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (26991901) 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 31 ways as a sum of consecutive naturals, for example, 23785 + ... + 24893.

It is an arithmetic number, because the mean of its divisors is an integer number (1376400).

Almost surely, 2^26991951 is an apocalyptic number.

26991951 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

26991951 is a deficient number, since it is larger than the sum of its proper divisors (17052849).

26991951 is a wasteful number, since it uses less digits than its factorization.

26991951 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1199.

The product of its digits is 43740, while the sum is 42.

The square root of 26991951 is about 5195.3778495890. The cubic root of 26991951 is about 299.9701859261.

The spelling of 26991951 in words is "twenty-six million, nine hundred ninety-one thousand, nine hundred fifty-one".