123535581 has 16 divisors (see below), whose sum is σ = 178481856. Its totient is φ = 75551616.

The previous prime is 123535561. The next prime is 123535609. The reversal of 123535581 is 185535321.

It is not a de Polignac number, because 123535581 - 2¹⁹ = 123011293 is a prime.

It is a super-2 number, since 2×123535581² = 30522079546015122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123535541) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3360 + ... + 16073.

It is an arithmetic number, because the mean of its divisors is an integer number (11155116).

Almost surely, 2^123535581 is an apocalyptic number.

It is an amenable number.

123535581 is a deficient number, since it is larger than the sum of its proper divisors (54946275).

123535581 is a wasteful number, since it uses less digits than its factorization.

123535581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19612.

The product of its digits is 18000, while the sum is 33.

The square root of 123535581 is about 11114.6561350318. The cubic root of 123535581 is about 498.0397663443.

The spelling of 123535581 in words is "one hundred twenty-three million, five hundred thirty-five thousand, five hundred eighty-one".