1211213201 has 4 divisors (see below), whose sum is σ = 1321323504. Its totient is φ = 1101102900.

The previous prime is 1211213191. The next prime is 1211213209. The reversal of 1211213201 is 1023121121.

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 1211213201 - 2⁶ = 1211213137 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1211213209) 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, 55055135 + ... + 55055156.

It is an arithmetic number, because the mean of its divisors is an integer number (330330876).

Almost surely, 2^1211213201 is an apocalyptic number.

1211213201 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1211213201 is a deficient number, since it is larger than the sum of its proper divisors (110110303).

1211213201 is a wasteful number, since it uses less digits than its factorization.

1211213201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110110302.

The product of its (nonzero) digits is 24, while the sum is 14.

The square root of 1211213201 is about 34802.4884311453. The cubic root of 1211213201 is about 1065.9582582184.

Adding to 1211213201 its reverse (1023121121), we get a palindrome (2234334322).

It can be divided in two parts, 1211 and 213201, that added together give a palindrome (214412).

The spelling of 1211213201 in words is "one billion, two hundred eleven million, two hundred thirteen thousand, two hundred one".