212991841 has 4 divisors (see below), whose sum is σ = 213035184. Its totient is φ = 212948500.

The previous prime is 212991839. The next prime is 212991853. The reversal of 212991841 is 148199212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 212991841 - 2¹ = 212991839 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 212991841.

It is not an unprimeable number, because it can be changed into a prime (212991041) 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 in 3 ways as a sum of consecutive naturals, for example, 13195 + ... + 24496.

It is an arithmetic number, because the mean of its divisors is an integer number (53258796).

Almost surely, 2^212991841 is an apocalyptic number.

It is an amenable number.

212991841 is a deficient number, since it is larger than the sum of its proper divisors (43343).

212991841 is an equidigital number, since it uses as much as digits as its factorization.

212991841 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43342.

The product of its digits is 10368, while the sum is 37.

The square root of 212991841 is about 14594.2399939154. The cubic root of 212991841 is about 597.2016364856.

The spelling of 212991841 in words is "two hundred twelve million, nine hundred ninety-one thousand, eight hundred forty-one".