1221338747727 has 24 divisors (see below), whose sum is σ = 2016225787680. Its totient is φ = 697891400640.

The previous prime is 1221338747683. The next prime is 1221338747731. The reversal of 1221338747727 is 7277478331221.

1221338747727 is a `hidden beast` number, since 1 + 2 + 213 + 387 + 47 + 7 + 2 + 7 = 666.

It is not a de Polignac number, because 1221338747727 - 2⁷ = 1221338747599 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221338747747) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2775577 + ... + 3185357.

It is an arithmetic number, because the mean of its divisors is an integer number (84009407820).

Almost surely, 2^{1221338747727} is an apocalyptic number.

1221338747727 is a deficient number, since it is larger than the sum of its proper divisors (794887039953).

1221338747727 is a wasteful number, since it uses less digits than its factorization.

1221338747727 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 457103 (or 457100 counting only the distinct ones).

The product of its digits is 5531904, while the sum is 54.

The spelling of 1221338747727 in words is "one trillion, two hundred twenty-one billion, three hundred thirty-eight million, seven hundred forty-seven thousand, seven hundred twenty-seven".