1221505323012 has 108 divisors (see below), whose sum is σ = 3345658108884. Its totient is φ = 375602872320.

The previous prime is 1221505322971. The next prime is 1221505323107. The reversal of 1221505323012 is 2103235051221.

1221505323012 is a `hidden beast` number, since 122 + 1 + 5 + 0 + 532 + 3 + 0 + 1 + 2 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 95941345536 + 1125563977476 = 309744^2 + 1060926^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 9383812 + ... + 9513092.

It is an arithmetic number, because the mean of its divisors is an integer number (30978315823).

Almost surely, 2^{1221505323012} is an apocalyptic number.

1221505323012 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 1221505323012, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1672829054442).

1221505323012 is an abundant number, since it is smaller than the sum of its proper divisors (2124152785872).

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

1221505323012 is a wasteful number, since it uses less digits than its factorization.

1221505323012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130870 (or 130852 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The spelling of 1221505323012 in words is "one trillion, two hundred twenty-one billion, five hundred five million, three hundred twenty-three thousand, twelve".