211220101 has 4 divisors (see below), whose sum is σ = 214195104. Its totient is φ = 208245100.

The previous prime is 211220099. The next prime is 211220117. The reversal of 211220101 is 101022112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 211220101 - 2¹ = 211220099 is a prime.

It is a super-2 number, since 2×211220101² = 89227862132900402, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211220501) 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, 1487395 + ... + 1487536.

It is an arithmetic number, because the mean of its divisors is an integer number (53548776).

Almost surely, 2^211220101 is an apocalyptic number.

It is an amenable number.

211220101 is a deficient number, since it is larger than the sum of its proper divisors (2975003).

211220101 is an equidigital number, since it uses as much as digits as its factorization.

211220101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2975002.

The product of its (nonzero) digits is 8, while the sum is 10.

The square root of 211220101 is about 14533.4132604836. The cubic root of 211220101 is about 595.5411135622.

Adding to 211220101 its reverse (101022112), we get a palindrome (312242213).

The spelling of 211220101 in words is "two hundred eleven million, two hundred twenty thousand, one hundred one".