1221513115264 has 192 divisors, whose sum is σ = 2667072744000. Its totient is φ = 556973654016.

The previous prime is 1221513115243. The next prime is 1221513115301. The reversal of 1221513115264 is 4625113151221.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 646644432 + ... + 646646320.

It is an arithmetic number, because the mean of its divisors is an integer number (13891003875).

Almost surely, 2^{1221513115264} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221513115264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1333536372000).

1221513115264 is an abundant number, since it is smaller than the sum of its proper divisors (1445559628736).

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

1221513115264 is a wasteful number, since it uses less digits than its factorization.

1221513115264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2275 (or 2250 counting only the distinct ones).

The product of its digits is 14400, while the sum is 34.

Adding to 1221513115264 its reverse (4625113151221), we get a palindrome (5846626266485).

The spelling of 1221513115264 in words is "one trillion, two hundred twenty-one billion, five hundred thirteen million, one hundred fifteen thousand, two hundred sixty-four".