2121213431 has 2 divisors, whose sum is σ = 2121213432. Its totient is φ = 2121213430.

The previous prime is 2121213427. The next prime is 2121213461. The reversal of 2121213431 is 1343121212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2121213431 - 2² = 2121213427 is a prime.

It is a super-2 number, since 2×2121213431² = 8999092839709583522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2121213461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1060606715 + 1060606716.

It is an arithmetic number, because the mean of its divisors is an integer number (1060606716).

Almost surely, 2^2121213431 is an apocalyptic number.

2121213431 is a deficient number, since it is larger than the sum of its proper divisors (1).

2121213431 is an equidigital number, since it uses as much as digits as its factorization.

2121213431 is an evil number, because the sum of its binary digits is even.

The product of its digits is 288, while the sum is 20.

The square root of 2121213431 is about 46056.6328665047. The cubic root of 2121213431 is about 1284.8767071723.

Adding to 2121213431 its reverse (1343121212), we get a palindrome (3464334643).

It can be divided in two parts, 21212 and 13431, that added together give a palindrome (34643).

The spelling of 2121213431 in words is "two billion, one hundred twenty-one million, two hundred thirteen thousand, four hundred thirty-one".