126581 has 12 divisors (see below), whose sum is σ = 158112. Its totient is φ = 99216.

The previous prime is 126551. The next prime is 126583. The reversal of 126581 is 185621.

126581 = T₁₃₃ + T₁₃₄ + ... + T₁₄₅.

It is not a de Polignac number, because 126581 - 2⁶ = 126517 is a prime.

It is a super-2 number, since 2×126581² = 32045499122, which contains 22 as substring.

It is a Smith number, since the sum of its digits (23) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is a plaindrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (126583) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1130 + ... + 1236.

It is an arithmetic number, because the mean of its divisors is an integer number (13176).

2¹²⁶⁵⁸¹ is an apocalyptic number.

It is an amenable number.

126581 is a deficient number, since it is larger than the sum of its proper divisors (31531).

126581 is a wasteful number, since it uses less digits than its factorization.

126581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140 (or 127 counting only the distinct ones).

The product of its digits is 480, while the sum is 23.

The square root of 126581 is about 355.7822367685. The cubic root of 126581 is about 50.2099174599.

It can be divided in two parts, 126 and 581, that added together give a palindrome (707).

The spelling of 126581 in words is "one hundred twenty-six thousand, five hundred eighty-one".