123531531 has 8 divisors (see below), whose sum is σ = 165428880. Its totient is φ = 81994272.

The previous prime is 123531511. The next prime is 123531533. The reversal of 123531531 is 135135321.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 123531531 - 2²² = 119337227 is a prime.

It is a super-2 number, since 2×123531531² = 30520078302407922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (123531533) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 89220 + ... + 90593.

It is an arithmetic number, because the mean of its divisors is an integer number (20678610).

Almost surely, 2^123531531 is an apocalyptic number.

123531531 is a deficient number, since it is larger than the sum of its proper divisors (41897349).

123531531 is a wasteful number, since it uses less digits than its factorization.

123531531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 180045.

The product of its digits is 1350, while the sum is 24.

The square root of 123531531 is about 11114.4739416672. The cubic root of 123531531 is about 498.0343236935.

Adding to 123531531 its reverse (135135321), we get a palindrome (258666852).

The spelling of 123531531 in words is "one hundred twenty-three million, five hundred thirty-one thousand, five hundred thirty-one".