212238391 has 2 divisors, whose sum is σ = 212238392. Its totient is φ = 212238390.

The previous prime is 212238361. The next prime is 212238413. The reversal of 212238391 is 193832212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 212238391 - 2¹⁷ = 212107319 is a prime.

It is a super-2 number, since 2×212238391² = 90090269228537762, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212238311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106119195 + 106119196.

It is an arithmetic number, because the mean of its divisors is an integer number (106119196).

Almost surely, 2^212238391 is an apocalyptic number.

212238391 is a deficient number, since it is larger than the sum of its proper divisors (1).

212238391 is an equidigital number, since it uses as much as digits as its factorization.

212238391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5184, while the sum is 31.

The square root of 212238391 is about 14568.4038590369. The cubic root of 212238391 is about 596.4966123093.

The spelling of 212238391 in words is "two hundred twelve million, two hundred thirty-eight thousand, three hundred ninety-one".