211921093 has 4 divisors (see below), whose sum is σ = 211951948. Its totient is φ = 211890240.

The previous prime is 211921051. The next prime is 211921111. The reversal of 211921093 is 390129112.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 132319009 + 79602084 = 11503^2 + 8922^2 .

It is a cyclic number.

It is not a de Polignac number, because 211921093 - 2²¹ = 209823941 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 (211921033) 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, 55 + ... + 20587.

It is an arithmetic number, because the mean of its divisors is an integer number (52987987).

Almost surely, 2^211921093 is an apocalyptic number.

It is an amenable number.

211921093 is a deficient number, since it is larger than the sum of its proper divisors (30855).

211921093 is a wasteful number, since it uses less digits than its factorization.

211921093 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30854.

The product of its (nonzero) digits is 972, while the sum is 28.

The square root of 211921093 is about 14557.5098488718. The cubic root of 211921093 is about 596.1992084038.

The spelling of 211921093 in words is "two hundred eleven million, nine hundred twenty-one thousand, ninety-three".