1231212505 has 8 divisors (see below), whose sum is σ = 1564364232. Its totient is φ = 927030528.

The previous prime is 1231212503. The next prime is 1231212511. The reversal of 1231212505 is 5052121321.

It can be written as a sum of positive squares in 4 ways, for example, as 130233744 + 1100978761 = 11412^2 + 33181^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 1231212505 - 2¹ = 1231212503 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1231212503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7242342 + ... + 7242511.

It is an arithmetic number, because the mean of its divisors is an integer number (195545529).

Almost surely, 2^1231212505 is an apocalyptic number.

It is an amenable number.

1231212505 is a deficient number, since it is larger than the sum of its proper divisors (333151727).

1231212505 is a wasteful number, since it uses less digits than its factorization.

1231212505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14484875.

The product of its (nonzero) digits is 600, while the sum is 22.

The square root of 1231212505 is about 35088.6378333500. The cubic root of 1231212505 is about 1071.7932212483.

Adding to 1231212505 its reverse (5052121321), we get a palindrome (6283333826).

The spelling of 1231212505 in words is "one billion, two hundred thirty-one million, two hundred twelve thousand, five hundred five".