1211231503421 has 2 divisors, whose sum is σ = 1211231503422. Its totient is φ = 1211231503420.

The previous prime is 1211231503409. The next prime is 1211231503529. The reversal of 1211231503421 is 1243051321121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1118276640196 + 92954863225 = 1057486^2 + 304885^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1211231503421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1211231503921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605615751710 + 605615751711.

It is an arithmetic number, because the mean of its divisors is an integer number (605615751711).

Almost surely, 2^{1211231503421} is an apocalyptic number.

It is an amenable number.

1211231503421 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211231503421 is an equidigital number, since it uses as much as digits as its factorization.

1211231503421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1440, while the sum is 26.

Adding to 1211231503421 its reverse (1243051321121), we get a palindrome (2454282824542).

The spelling of 1211231503421 in words is "one trillion, two hundred eleven billion, two hundred thirty-one million, five hundred three thousand, four hundred twenty-one".