212290991 has 24 divisors (see below), whose sum is σ = 244188000. Its totient is φ = 184184000.

The previous prime is 212290987. The next prime is 212290993. The reversal of 212290991 is 199092212.

It is not a de Polignac number, because 212290991 - 2² = 212290987 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 (212290993) 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 23 ways as a sum of consecutive naturals, for example, 354110 + ... + 354708.

It is an arithmetic number, because the mean of its divisors is an integer number (10174500).

Almost surely, 2^212290991 is an apocalyptic number.

212290991 is a deficient number, since it is larger than the sum of its proper divisors (31897009).

212290991 is a wasteful number, since it uses less digits than its factorization.

212290991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 751 (or 740 counting only the distinct ones).

The product of its (nonzero) digits is 5832, while the sum is 35.

The square root of 212290991 is about 14570.2090238953. The cubic root of 212290991 is about 596.5458857231.

The spelling of 212290991 in words is "two hundred twelve million, two hundred ninety thousand, nine hundred ninety-one".