1221331683936 has 768 divisors, whose sum is σ = 4333472317440. Its totient is φ = 292148674560.

The previous prime is 1221331683823. The next prime is 1221331683997. The reversal of 1221331683936 is 6393861331221.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 499112665 + ... + 499115111.

It is an arithmetic number, because the mean of its divisors is an integer number (5642542080).

Almost surely, 2^{1221331683936} is an apocalyptic number.

1221331683936 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221331683936, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2166736158720).

1221331683936 is an abundant number, since it is smaller than the sum of its proper divisors (3112140633504).

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

1221331683936 is a wasteful number, since it uses less digits than its factorization.

1221331683936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2627 (or 2619 counting only the distinct ones).

The product of its digits is 839808, while the sum is 48.

The spelling of 1221331683936 in words is "one trillion, two hundred twenty-one billion, three hundred thirty-one million, six hundred eighty-three thousand, nine hundred thirty-six".