212442991 has 2 divisors, whose sum is σ = 212442992. Its totient is φ = 212442990.

The previous prime is 212442947. The next prime is 212443001. The reversal of 212442991 is 199244212.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 212442991 - 2⁹ = 212442479 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212442941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106221495 + 106221496.

It is an arithmetic number, because the mean of its divisors is an integer number (106221496).

Almost surely, 2^212442991 is an apocalyptic number.

212442991 is a deficient number, since it is larger than the sum of its proper divisors (1).

212442991 is an equidigital number, since it uses as much as digits as its factorization.

212442991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10368, while the sum is 34.

The square root of 212442991 is about 14575.4242133805. The cubic root of 212442991 is about 596.6882270471.

The spelling of 212442991 in words is "two hundred twelve million, four hundred forty-two thousand, nine hundred ninety-one".