12400531 has 16 divisors (see below), whose sum is σ = 15428448. Its totient is φ = 9792000.

The previous prime is 12400517. The next prime is 12400541. The reversal of 12400531 is 13500421.

It is not a de Polignac number, because 12400531 - 2¹¹ = 12398483 is a prime.

It is a super-2 number, since 2×12400531² = 307546338163922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12400511) 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, 120 + ... + 4981.

It is an arithmetic number, because the mean of its divisors is an integer number (964278).

Almost surely, 2^12400531 is an apocalyptic number.

12400531 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

12400531 is a deficient number, since it is larger than the sum of its proper divisors (3027917).

12400531 is a wasteful number, since it uses less digits than its factorization.

12400531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5142.

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 12400531 is about 3521.4387684581. The cubic root of 12400531 is about 231.4622092946.

Adding to 12400531 its reverse (13500421), we get a palindrome (25900952).

The spelling of 12400531 in words is "twelve million, four hundred thousand, five hundred thirty-one".