213221022491 has 2 divisors, whose sum is σ = 213221022492. Its totient is φ = 213221022490.

The previous prime is 213221022457. The next prime is 213221022517. The reversal of 213221022491 is 194220122312.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 213221022491 - 2³⁴ = 196041153307 is a prime.

It is not a weakly prime, because it can be changed into another prime (213221022431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106610511245 + 106610511246.

It is an arithmetic number, because the mean of its divisors is an integer number (106610511246).

Almost surely, 2^213221022491 is an apocalyptic number.

213221022491 is a deficient number, since it is larger than the sum of its proper divisors (1).

213221022491 is an equidigital number, since it uses as much as digits as its factorization.

213221022491 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3456, while the sum is 29.

The spelling of 213221022491 in words is "two hundred thirteen billion, two hundred twenty-one million, twenty-two thousand, four hundred ninety-one".