213012991 has 2 divisors, whose sum is σ = 213012992. Its totient is φ = 213012990.

The previous prime is 213012973. The next prime is 213013049. The reversal of 213012991 is 199210312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 213012991 - 2¹⁷ = 212881919 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (213012901) 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 as a sum of consecutive naturals, namely, 106506495 + 106506496.

It is an arithmetic number, because the mean of its divisors is an integer number (106506496).

Almost surely, 2^213012991 is an apocalyptic number.

213012991 is a deficient number, since it is larger than the sum of its proper divisors (1).

213012991 is an equidigital number, since it uses as much as digits as its factorization.

213012991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 972, while the sum is 28.

The square root of 213012991 is about 14594.9645768669. The cubic root of 213012991 is about 597.2214031216.

The spelling of 213012991 in words is "two hundred thirteen million, twelve thousand, nine hundred ninety-one".