1221212011236 has 48 divisors (see below), whose sum is σ = 3257291178624. Its totient is φ = 348839951616.

The previous prime is 1221212011157. The next prime is 1221212011259. The reversal of 1221212011236 is 6321102121221.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1240465 + ... + 1995288.

It is an arithmetic number, because the mean of its divisors is an integer number (67860232888).

Almost surely, 2^{1221212011236} is an apocalyptic number.

It is an amenable number.

1221212011236 is an abundant number, since it is smaller than the sum of its proper divisors (2036079167388).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1221212011236 is a wasteful number, since it uses less digits than its factorization.

1221212011236 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3240260 (or 3240258 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 24.

Adding to 1221212011236 its reverse (6321102121221), we get a palindrome (7542314132457).

The spelling of 1221212011236 in words is "one trillion, two hundred twenty-one billion, two hundred twelve million, eleven thousand, two hundred thirty-six".