1221075211 has 8 divisors (see below), whose sum is σ = 1225058384. Its totient is φ = 1217099520.

The previous prime is 1221075203. The next prime is 1221075227. The reversal of 1221075211 is 1125701221.

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 1221075211 - 2³ = 1221075203 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221075281) 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, 563971 + ... + 566131.

It is an arithmetic number, because the mean of its divisors is an integer number (153132298).

Almost surely, 2^1221075211 is an apocalyptic number.

1221075211 is a deficient number, since it is larger than the sum of its proper divisors (3983173).

1221075211 is a wasteful number, since it uses less digits than its factorization.

1221075211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3741.

The product of its (nonzero) digits is 280, while the sum is 22.

The square root of 1221075211 is about 34943.8866040971. The cubic root of 1221075211 is about 1068.8435436926.

Adding to 1221075211 its reverse (1125701221), we get a palindrome (2346776432).

The spelling of 1221075211 in words is "one billion, two hundred twenty-one million, seventy-five thousand, two hundred eleven".