1221059634318 has 48 divisors (see below), whose sum is σ = 2671634374656. Its totient is φ = 403020029520.

The previous prime is 1221059634271. The next prime is 1221059634323. The reversal of 1221059634318 is 8134369501221.

1221059634318 is a `hidden beast` number, since 1 + 2 + 2 + 1 + 0 + 5 + 9 + 634 + 3 + 1 + 8 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17598771 + ... + 17668017.

It is an arithmetic number, because the mean of its divisors is an integer number (55659049472).

Almost surely, 2^{1221059634318} is an apocalyptic number.

1221059634318 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1221059634318 is an abundant number, since it is smaller than the sum of its proper divisors (1450574740338).

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

1221059634318 is a wasteful number, since it uses less digits than its factorization.

1221059634318 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78869 (or 78866 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The spelling of 1221059634318 in words is "one trillion, two hundred twenty-one billion, fifty-nine million, six hundred thirty-four thousand, three hundred eighteen".