2181206 has 8 divisors (see below), whose sum is σ = 3384720. Its totient is φ = 1052968.

The previous prime is 2181203. The next prime is 2181209. The reversal of 2181206 is 6021812.

It is an interprime number because it is at equal distance from previous prime (2181203) and next prime (2181209).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×2181206² = 9515319228872, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2181203) 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, 18746 + ... + 18861.

It is an arithmetic number, because the mean of its divisors is an integer number (423090).

2^2181206 is an apocalyptic number.

2181206 is a deficient number, since it is larger than the sum of its proper divisors (1203514).

2181206 is a wasteful number, since it uses less digits than its factorization.

2181206 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37638.

The product of its (nonzero) digits is 192, while the sum is 20.

The square root of 2181206 is about 1476.8906526890. The cubic root of 2181206 is about 129.6877317749.

Subtracting 2181206 from its reverse (6021812), we obtain a triangular number (3840606 = T₂₇₇₁).

The spelling of 2181206 in words is "two million, one hundred eighty-one thousand, two hundred six".