1211010009 has 32 divisors (see below), whose sum is σ = 1844011008. Its totient is φ = 700224000.

The previous prime is 1211009951. The next prime is 1211010029. The reversal of 1211010009 is 9000101121.

It is not a de Polignac number, because 1211010009 - 2¹¹ = 1211007961 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1211010009.

It is not an unprimeable number, because it can be changed into a prime (1211010029) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 64297 + ... + 80969.

It is an arithmetic number, because the mean of its divisors is an integer number (57625344).

Almost surely, 2^1211010009 is an apocalyptic number.

It is an amenable number.

1211010009 is a deficient number, since it is larger than the sum of its proper divisors (633000999).

1211010009 is a wasteful number, since it uses less digits than its factorization.

1211010009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16789.

The product of its (nonzero) digits is 18, while the sum is 15.

The square root of 1211010009 is about 34799.5690921597. The cubic root of 1211010009 is about 1065.8986468295.

The spelling of 1211010009 in words is "one billion, two hundred eleven million, ten thousand, nine".