210990 has 32 divisors (see below), whose sum is σ = 546336. Its totient is φ = 51840.

The previous prime is 210967. The next prime is 211007. The reversal of 210990 is 99012.

It is a happy number.

210990 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a plaindrome in base 11.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 120 + ... + 660.

It is an arithmetic number, because the mean of its divisors is an integer number (17073).

2²¹⁰⁹⁹⁰ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 210990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (273168).

210990 is an abundant number, since it is smaller than the sum of its proper divisors (335346).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

210990 is a wasteful number, since it uses less digits than its factorization.

210990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 564.

The product of its (nonzero) digits is 162, while the sum is 21.

The square root of 210990 is about 459.3364779767. The cubic root of 210990 is about 59.5324776202.

The spelling of 210990 in words is "two hundred ten thousand, nine hundred ninety".