1211010101 has 16 divisors (see below), whose sum is σ = 1432909440. Its totient is φ = 1001394240.

The previous prime is 1211010077. The next prime is 1211010103. The reversal of 1211010101 is 1010101121.

It is a happy number.

It is not a de Polignac number, because 1211010101 - 2¹⁰ = 1211009077 is a prime.

It is a Duffinian number.

1211010101 is a modest number, since divided by 10101 gives 1211 as remainder.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211010103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 477206 + ... + 479736.

It is an arithmetic number, because the mean of its divisors is an integer number (89556840).

Almost surely, 2^1211010101 is an apocalyptic number.

It is an amenable number.

1211010101 is a deficient number, since it is larger than the sum of its proper divisors (221899339).

1211010101 is a wasteful number, since it uses less digits than its factorization.

1211010101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4924.

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

The square root of 1211010101 is about 34799.5704140152. The cubic root of 1211010101 is about 1065.8986738215.

Adding to 1211010101 its reverse (1010101121), we get a palindrome (2221111222).

It can be divided in two parts, 121 and 1010101, that multiplied together give a palindrome (122222221).

The spelling of 1211010101 in words is "one billion, two hundred eleven million, ten thousand, one hundred one".