1211012311 has 16 divisors (see below), whose sum is σ = 1259104000. Its totient is φ = 1163973888.

The previous prime is 1211012269. The next prime is 1211012351. The reversal of 1211012311 is 1132101121.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1211012311 - 2⁹ = 1211011799 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1211012291 and 1211012300.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211012351) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 829300 + ... + 830758.

It is an arithmetic number, because the mean of its divisors is an integer number (78694000).

Almost surely, 2^1211012311 is an apocalyptic number.

1211012311 is a deficient number, since it is larger than the sum of its proper divisors (48091689).

1211012311 is a wasteful number, since it uses less digits than its factorization.

1211012311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1798.

The product of its (nonzero) digits is 12, while the sum is 13.

The square root of 1211012311 is about 34799.6021672662. The cubic root of 1211012311 is about 1065.8993222154.

Adding to 1211012311 its reverse (1132101121), we get a palindrome (2343113432).

The spelling of 1211012311 in words is "one billion, two hundred eleven million, twelve thousand, three hundred eleven".