212644991 has 8 divisors (see below), whose sum is σ = 229121760. Its totient is φ = 196185312.

The previous prime is 212644987. The next prime is 212645003. The reversal of 212644991 is 199446212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 212644991 - 2² = 212644987 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211644991) 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 7 ways as a sum of consecutive naturals, for example, 35006 + ... + 40628.

It is an arithmetic number, because the mean of its divisors is an integer number (28640220).

Almost surely, 2^212644991 is an apocalyptic number.

212644991 is a deficient number, since it is larger than the sum of its proper divisors (16476769).

212644991 is a wasteful number, since it uses less digits than its factorization.

212644991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8545.

The product of its digits is 31104, while the sum is 38.

The square root of 212644991 is about 14582.3520393659. The cubic root of 212644991 is about 596.8772861439.

The spelling of 212644991 in words is "two hundred twelve million, six hundred forty-four thousand, nine hundred ninety-one".