211721090 has 32 divisors (see below), whose sum is σ = 436385664. Its totient is φ = 72449280.

The previous prime is 211721063. The next prime is 211721093. The reversal of 211721090 is 90127112.

211721090 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (211721093) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 37322 + ... + 42618.

It is an arithmetic number, because the mean of its divisors is an integer number (13637052).

Almost surely, 2^211721090 is an apocalyptic number.

211721090 is an abundant number, since it is smaller than the sum of its proper divisors (224664574).

211721090 is a wasteful number, since it uses less digits than its factorization.

211721090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5882.

The product of its (nonzero) digits is 252, while the sum is 23.

The square root of 211721090 is about 14550.6388175915. The cubic root of 211721090 is about 596.0115927208.

The spelling of 211721090 in words is "two hundred eleven million, seven hundred twenty-one thousand, ninety".