212121919 has 2 divisors, whose sum is σ = 212121920. Its totient is φ = 212121918.

The previous prime is 212121911. The next prime is 212121929. The reversal of 212121919 is 919121212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 212121919 - 2³ = 212121911 is a prime.

It is a super-2 number, since 2×212121919² = 89991417040485122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212121911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106060959 + 106060960.

It is an arithmetic number, because the mean of its divisors is an integer number (106060960).

Almost surely, 2^212121919 is an apocalyptic number.

212121919 is a deficient number, since it is larger than the sum of its proper divisors (1).

212121919 is an equidigital number, since it uses as much as digits as its factorization.

212121919 is an evil number, because the sum of its binary digits is even.

The product of its digits is 648, while the sum is 28.

The square root of 212121919 is about 14564.4058924489. The cubic root of 212121919 is about 596.3874773788.

The spelling of 212121919 in words is "two hundred twelve million, one hundred twenty-one thousand, nine hundred nineteen".