211012121 has 4 divisors (see below), whose sum is σ = 213902772. Its totient is φ = 208121472.

The previous prime is 211012103. The next prime is 211012127. The reversal of 211012121 is 121210112.

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

It can be written as a sum of positive squares in 2 ways, for example, as 174530521 + 36481600 = 13211^2 + 6040^2 .

It is a cyclic number.

It is not a de Polignac number, because 211012121 - 2⁶ = 211012057 is a prime.

It is a super-2 number, since 2×211012121² = 89052230417837282, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (211012127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1445216 + ... + 1445361.

It is an arithmetic number, because the mean of its divisors is an integer number (53475693).

Almost surely, 2^211012121 is an apocalyptic number.

It is an amenable number.

211012121 is a deficient number, since it is larger than the sum of its proper divisors (2890651).

211012121 is an equidigital number, since it uses as much as digits as its factorization.

211012121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2890650.

The product of its (nonzero) digits is 8, while the sum is 11.

The square root of 211012121 is about 14526.2562623685. The cubic root of 211012121 is about 595.3455808517.

Adding to 211012121 its reverse (121210112), we get a palindrome (332222233).

The spelling of 211012121 in words is "two hundred eleven million, twelve thousand, one hundred twenty-one".