211172081878 has 4 divisors (see below), whose sum is σ = 316758122820. Its totient is φ = 105586040938.

The previous prime is 211172081863. The next prime is 211172081909. The reversal of 211172081878 is 878180271112.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 52793020468 + ... + 52793020471.

It is an arithmetic number, because the mean of its divisors is an integer number (79189530705).

Almost surely, 2^211172081878 is an apocalyptic number.

211172081878 is a deficient number, since it is larger than the sum of its proper divisors (105586040942).

211172081878 is a wasteful number, since it uses less digits than its factorization.

211172081878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105586040941.

The product of its (nonzero) digits is 100352, while the sum is 46.

The spelling of 211172081878 in words is "two hundred eleven billion, one hundred seventy-two million, eighty-one thousand, eight hundred seventy-eight".