21212001120931 has 2 divisors, whose sum is σ = 21212001120932. Its totient is φ = 21212001120930.

The previous prime is 21212001120901. The next prime is 21212001121033. The reversal of 21212001120931 is 13902110021212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21212001120931 - 2⁵ = 21212001120899 is a prime.

It is a super-2 number, since 2×21212001120931² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21212001120896 and 21212001120905.

It is not a weakly prime, because it can be changed into another prime (21212001120901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606000560465 + 10606000560466.

It is an arithmetic number, because the mean of its divisors is an integer number (10606000560466).

Almost surely, 2^{21212001120931} is an apocalyptic number.

21212001120931 is a deficient number, since it is larger than the sum of its proper divisors (1).

21212001120931 is an equidigital number, since it uses as much as digits as its factorization.

21212001120931 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 25.

The spelling of 21212001120931 in words is "twenty-one trillion, two hundred twelve billion, one million, one hundred twenty thousand, nine hundred thirty-one".