1211871 has 4 divisors (see below), whose sum is σ = 1615832. Its totient is φ = 807912.

The previous prime is 1211863. The next prime is 1211897. The reversal of 1211871 is 1781121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1781121 = 3 ⋅593707.

It is not a de Polignac number, because 1211871 - 2³ = 1211863 is a prime.

It is a D-number.

It is a Duffinian number.

It is a plaindrome in base 13 and base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1210871) 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, 201976 + ... + 201981.

It is an arithmetic number, because the mean of its divisors is an integer number (403958).

2^1211871 is an apocalyptic number.

1211871 is a deficient number, since it is larger than the sum of its proper divisors (403961).

1211871 is an equidigital number, since it uses as much as digits as its factorization.

1211871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 403960.

The product of its digits is 112, while the sum is 21.

The square root of 1211871 is about 1100.8501260390. The cubic root of 1211871 is about 106.6151194077.

Adding to 1211871 its reverse (1781121), we get a palindrome (2992992).

The spelling of 1211871 in words is "one million, two hundred eleven thousand, eight hundred seventy-one".