12531156405 has 8 divisors (see below), whose sum is σ = 20049850272. Its totient is φ = 6683283408.

The previous prime is 12531156383. The next prime is 12531156409. The reversal of 12531156405 is 50465113521.

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

It is not a de Polignac number, because 12531156405 - 2⁸ = 12531156149 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12531156409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 417705199 + ... + 417705228.

It is an arithmetic number, because the mean of its divisors is an integer number (2506231284).

Almost surely, 2^12531156405 is an apocalyptic number.

12531156405 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

12531156405 is a deficient number, since it is larger than the sum of its proper divisors (7518693867).

12531156405 is an equidigital number, since it uses as much as digits as its factorization.

12531156405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 835410435.

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

Adding to 12531156405 its reverse (50465113521), we get a palindrome (62996269926).

The spelling of 12531156405 in words is "twelve billion, five hundred thirty-one million, one hundred fifty-six thousand, four hundred five".