1211201101 has 4 divisors (see below), whose sum is σ = 1321310304. Its totient is φ = 1101091900.

The previous prime is 1211201087. The next prime is 1211201107. The reversal of 1211201101 is 1011021121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1211201101 - 2⁷ = 1211200973 is a prime.

It is a super-2 number, since 2×1211201101² = 2934016214127224402, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211201107) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55054585 + ... + 55054606.

It is an arithmetic number, because the mean of its divisors is an integer number (330327576).

Almost surely, 2^1211201101 is an apocalyptic number.

1211201101 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1211201101 is a deficient number, since it is larger than the sum of its proper divisors (110109203).

1211201101 is a wasteful number, since it uses less digits than its factorization.

1211201101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110109202.

The product of its (nonzero) digits is 4, while the sum is 10.

The square root of 1211201101 is about 34802.3145925670. The cubic root of 1211201101 is about 1065.9547085714.

Adding to 1211201101 its reverse (1011021121), we get a palindrome (2222222222).

It can be divided in two parts, 121120 and 1101, that added together give a palindrome (122221).

The spelling of 1211201101 in words is "one billion, two hundred eleven million, two hundred one thousand, one hundred one".