1221322011 has 96 divisors (see below), whose sum is σ = 2189150208. Its totient is φ = 598752000.

The previous prime is 1221321977. The next prime is 1221322013. The reversal of 1221322011 is 1102231221.

1221322011 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 1221322011 - 2⁶ = 1221321947 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1221322013) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1625886 + ... + 1626636.

It is an arithmetic number, because the mean of its divisors is an integer number (22803648).

Almost surely, 2^1221322011 is an apocalyptic number.

1221322011 is a deficient number, since it is larger than the sum of its proper divisors (967828197).

1221322011 is a wasteful number, since it uses less digits than its factorization.

1221322011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 841 (or 834 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 15.

The square root of 1221322011 is about 34947.4178016059. The cubic root of 1221322011 is about 1068.9155493081.

Adding to 1221322011 its reverse (1102231221), we get a palindrome (2323553232).

The spelling of 1221322011 in words is "one billion, two hundred twenty-one million, three hundred twenty-two thousand, eleven".