1221686324352 has 192 divisors, whose sum is σ = 3795230657400. Its totient is φ = 374982524928.

The previous prime is 1221686324347. The next prime is 1221686324371. The reversal of 1221686324352 is 2534236861221.

1221686324352 is a `hidden beast` number, since 1 + 2 + 2 + 1 + 6 + 8 + 632 + 4 + 3 + 5 + 2 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 840918344256 + 380767980096 = 917016^2 + 617064^2 .

It is a tau number, because it is divible by the number of its divisors (192).

It is a junction number, because it is equal to n+sod(n) for n = 1221686324298 and 1221686324307.

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, 6025458 + ... + 6224910.

Almost surely, 2^{1221686324352} is an apocalyptic number.

1221686324352 is a gapful number since it is divisible by the number (12) 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 1221686324352, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1897615328700).

1221686324352 is an abundant number, since it is smaller than the sum of its proper divisors (2573544333048).

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

1221686324352 is a wasteful number, since it uses less digits than its factorization.

1221686324352 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199895 (or 199880 counting only the distinct ones).

The product of its digits is 829440, while the sum is 45.

The spelling of 1221686324352 in words is "one trillion, two hundred twenty-one billion, six hundred eighty-six million, three hundred twenty-four thousand, three hundred fifty-two".