212639197 has 4 divisors (see below), whose sum is σ = 213592960. Its totient is φ = 211685436.

The previous prime is 212639177. The next prime is 212639201. The reversal of 212639197 is 791936212.

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 a de Polignac number, because none of the positive numbers 2^k-212639197 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 (212639177) 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, 476547 + ... + 476992.

It is an arithmetic number, because the mean of its divisors is an integer number (53398240).

Almost surely, 2^212639197 is an apocalyptic number.

It is an amenable number.

212639197 is a deficient number, since it is larger than the sum of its proper divisors (953763).

212639197 is an equidigital number, since it uses as much as digits as its factorization.

212639197 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 953762.

The product of its digits is 40824, while the sum is 40.

The square root of 212639197 is about 14582.1533732162. The cubic root of 212639197 is about 596.8718649982.

The spelling of 212639197 in words is "two hundred twelve million, six hundred thirty-nine thousand, one hundred ninety-seven".