26261991 has 72 divisors (see below), whose sum is σ = 48657024. Its totient is φ = 13547520.

The previous prime is 26261987. The next prime is 26261999. The reversal of 26261991 is 19916262.

It is not a de Polignac number, because 26261991 - 2² = 26261987 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (26261999) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 232351 + ... + 232463.

It is an arithmetic number, because the mean of its divisors is an integer number (675792).

Almost surely, 2^26261991 is an apocalyptic number.

26261991 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

26261991 is a deficient number, since it is larger than the sum of its proper divisors (22395033).

26261991 is a wasteful number, since it uses less digits than its factorization.

26261991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 181 (or 171 counting only the distinct ones).

The product of its digits is 11664, while the sum is 36.

The square root of 26261991 is about 5124.6454511507. The cubic root of 26261991 is about 297.2413438085.

The spelling of 26261991 in words is "twenty-six million, two hundred sixty-one thousand, nine hundred ninety-one".