1211001011 has 8 divisors (see below), whose sum is σ = 1321632624. Its totient is φ = 1100459520.

The previous prime is 1211000971. The next prime is 1211001023. The reversal of 1211001011 is 1101001121.

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 1211001011 - 2¹⁰ = 1210999987 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1211001011.

It is not an unprimeable number, because it can be changed into a prime (1211001031) 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, 7295 + ... + 49751.

It is an arithmetic number, because the mean of its divisors is an integer number (165204078).

Almost surely, 2^1211001011 is an apocalyptic number.

1211001011 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1211001011 is a deficient number, since it is larger than the sum of its proper divisors (110631613).

1211001011 is a wasteful number, since it uses less digits than its factorization.

1211001011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45061.

The product of its (nonzero) digits is 2, while the sum is 8.

The square root of 1211001011 is about 34799.4398087096. The cubic root of 1211001011 is about 1065.8960068899.

Adding to 1211001011 its reverse (1101001121), we get a palindrome (2312002132).

The spelling of 1211001011 in words is "one billion, two hundred eleven million, one thousand, eleven".