212113381 has 2 divisors, whose sum is σ = 212113382. Its totient is φ = 212113380.

The previous prime is 212113379. The next prime is 212113393. The reversal of 212113381 is 183311212.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 211702500 + 410881 = 14550^2 + 641^2 .

It is a cyclic number.

It is not a de Polignac number, because 212113381 - 2¹ = 212113379 is a prime.

It is a super-2 number, since 2×212113381² = 89984172798502322, which contains 22 as substring.

Together with 212113379, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212113081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106056690 + 106056691.

It is an arithmetic number, because the mean of its divisors is an integer number (106056691).

Almost surely, 2^212113381 is an apocalyptic number.

It is an amenable number.

212113381 is a deficient number, since it is larger than the sum of its proper divisors (1).

212113381 is an equidigital number, since it uses as much as digits as its factorization.

212113381 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 288, while the sum is 22.

The square root of 212113381 is about 14564.1127776463. The cubic root of 212113381 is about 596.3794756525.

Adding to 212113381 its reverse (183311212), we get a palindrome (395424593).

The spelling of 212113381 in words is "two hundred twelve million, one hundred thirteen thousand, three hundred eighty-one".