211451825861 has 4 divisors (see below), whose sum is σ = 211466867424. Its totient is φ = 211436784300.

The previous prime is 211451825843. The next prime is 211451825891. The reversal of 211451825861 is 168528154112.

211451825861 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 not a de Polignac number, because 211451825861 - 2¹⁴ = 211451809477 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 (211451825891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7499675 + ... + 7527816.

It is an arithmetic number, because the mean of its divisors is an integer number (52866716856).

Almost surely, 2^211451825861 is an apocalyptic number.

It is an amenable number.

211451825861 is a deficient number, since it is larger than the sum of its proper divisors (15041563).

211451825861 is a wasteful number, since it uses less digits than its factorization.

211451825861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15041562.

The product of its digits is 153600, while the sum is 44.

Adding to 211451825861 its reverse (168528154112), we get a palindrome (379979979973).

The spelling of 211451825861 in words is "two hundred eleven billion, four hundred fifty-one million, eight hundred twenty-five thousand, eight hundred sixty-one".