211158499861 has 4 divisors (see below), whose sum is σ = 211159795500. Its totient is φ = 211157204224.

The previous prime is 211158499829. The next prime is 211158499873. The reversal of 211158499861 is 168994851112.

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

It can be written as a sum of positive squares in 2 ways, for example, as 105751137636 + 105407362225 = 325194^2 + 324665^2 .

It is a cyclic number.

It is not a de Polignac number, because 211158499861 - 2⁵ = 211158499829 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 (211158499801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 361036 + ... + 743413.

It is an arithmetic number, because the mean of its divisors is an integer number (52789948875).

Almost surely, 2^211158499861 is an apocalyptic number.

It is an amenable number.

211158499861 is a deficient number, since it is larger than the sum of its proper divisors (1295639).

211158499861 is a wasteful number, since it uses less digits than its factorization.

211158499861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1295638.

The product of its digits is 1244160, while the sum is 55.

The spelling of 211158499861 in words is "two hundred eleven billion, one hundred fifty-eight million, four hundred ninety-nine thousand, eight hundred sixty-one".