1211331011 has 8 divisors (see below), whose sum is σ = 1321711104. Its totient is φ = 1100994120.

The previous prime is 1211331007. The next prime is 1211331031. The reversal of 1211331011 is 1101331121.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 1211331011 - 2² = 1211331007 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1211331031) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 84230 + ... + 97556.

It is an arithmetic number, because the mean of its divisors is an integer number (165213888).

Almost surely, 2^1211331011 is an apocalyptic number.

1211331011 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1211331011 is a deficient number, since it is larger than the sum of its proper divisors (110380093).

1211331011 is a wasteful number, since it uses less digits than its factorization.

1211331011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21601.

The product of its (nonzero) digits is 18, while the sum is 14.

The square root of 1211331011 is about 34804.1809413754. The cubic root of 1211331011 is about 1065.9928176367.

Adding to 1211331011 its reverse (1101331121), we get a palindrome (2312662132).

The spelling of 1211331011 in words is "one billion, two hundred eleven million, three hundred thirty-one thousand, eleven".