1211211212431 has 16 divisors (see below), whose sum is σ = 1390917939840. Its totient is φ = 1043108370720.

The previous prime is 1211211212381. The next prime is 1211211212437. The reversal of 1211211212431 is 1342121121121.

It is a cyclic number.

It is not a de Polignac number, because 1211211212431 - 2⁹ = 1211211211919 is a prime.

It is a super-2 number, since 2×1211211212431² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211211212437) 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 15 ways as a sum of consecutive naturals, for example, 6201636 + ... + 6393958.

It is an arithmetic number, because the mean of its divisors is an integer number (86932371240).

Almost surely, 2^{1211211212431} is an apocalyptic number.

1211211212431 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1211211212431 is a deficient number, since it is larger than the sum of its proper divisors (179706727409).

1211211212431 is a wasteful number, since it uses less digits than its factorization.

1211211212431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222486.

The product of its digits is 192, while the sum is 22.

Adding to 1211211212431 its reverse (1342121121121), we get a palindrome (2553332333552).

The spelling of 1211211212431 in words is "one trillion, two hundred eleven billion, two hundred eleven million, two hundred twelve thousand, four hundred thirty-one".