201801211 has 4 divisors (see below), whose sum is σ = 201918472. Its totient is φ = 201683952.

The previous prime is 201801209. The next prime is 201801217. The reversal of 201801211 is 112108102.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 201801211 - 2¹ = 201801209 is a prime.

It is a super-2 number, since 2×201801211² = 81447457522133042, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (201801217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 56010 + ... + 59503.

It is an arithmetic number, because the mean of its divisors is an integer number (50479618).

Almost surely, 2^201801211 is an apocalyptic number.

201801211 is a deficient number, since it is larger than the sum of its proper divisors (117261).

201801211 is a wasteful number, since it uses less digits than its factorization.

201801211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 117260.

The product of its (nonzero) digits is 32, while the sum is 16.

The square root of 201801211 is about 14205.6753095374. The cubic root of 201801211 is about 586.5538945097.

Adding to 201801211 its reverse (112108102), we get a palindrome (313909313).

The spelling of 201801211 in words is "two hundred one million, eight hundred one thousand, two hundred eleven".