26690 has 16 divisors (see below), whose sum is σ = 51192. Its totient is φ = 9984.

The previous prime is 26687. The next prime is 26693. The reversal of 26690 is 9662.

26690 = T₅₂ + T₅₃ + ... + T₆₆.

It is an interprime number because it is at equal distance from previous prime (26687) and next prime (26693).

It can be written as a sum of positive squares in 4 ways, for example, as 22201 + 4489 = 149^2 + 67^2 .

It is a super-2 number, since 2×26690² = 1424712200, which contains 22 as substring.

26690 is an undulating number in base 13.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (26693) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 92 + ... + 248.

2²⁶⁶⁹⁰ is an apocalyptic number.

26690 is a deficient number, since it is larger than the sum of its proper divisors (24502).

26690 is a wasteful number, since it uses less digits than its factorization.

26690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 181.

The product of its (nonzero) digits is 648, while the sum is 23.

The square root of 26690 is about 163.3707440150. The cubic root of 26690 is about 29.8847429460.

The spelling of 26690 in words is "twenty-six thousand, six hundred ninety".