212840091 has 12 divisors (see below), whose sum is σ = 320802768. Its totient is φ = 135723984.

The previous prime is 212840083. The next prime is 212840107. The reversal of 212840091 is 190048212.

It is not a de Polignac number, because 212840091 - 2³ = 212840083 is a prime.

It is not an unprimeable number, because it can be changed into a prime (212840191) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 513900 + ... + 514313.

It is an arithmetic number, because the mean of its divisors is an integer number (26733564).

Almost surely, 2^212840091 is an apocalyptic number.

212840091 is a deficient number, since it is larger than the sum of its proper divisors (107962677).

212840091 is a wasteful number, since it uses less digits than its factorization.

212840091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1028242 (or 1028239 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 212840091 is about 14589.0400986494. The cubic root of 212840091 is about 597.0597736503.

The spelling of 212840091 in words is "two hundred twelve million, eight hundred forty thousand, ninety-one".