211540598081 has 4 divisors (see below), whose sum is σ = 223984162692. Its totient is φ = 199097033472.

The previous prime is 211540598069. The next prime is 211540598089. The reversal of 211540598081 is 180895045112.

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 136911100225 + 74629497856 = 370015^2 + 273184^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-211540598081 is a prime.

It is a super-2 number, since 2×211540598081² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (211540598089) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6221782280 + ... + 6221782313.

It is an arithmetic number, because the mean of its divisors is an integer number (55996040673).

Almost surely, 2^211540598081 is an apocalyptic number.

It is an amenable number.

211540598081 is a deficient number, since it is larger than the sum of its proper divisors (12443564611).

211540598081 is a wasteful number, since it uses less digits than its factorization.

211540598081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12443564610.

The product of its (nonzero) digits is 115200, while the sum is 44.

The spelling of 211540598081 in words is "two hundred eleven billion, five hundred forty million, five hundred ninety-eight thousand, eighty-one".