1215221755993 has 8 divisors (see below), whose sum is σ = 1390951706688. Its totient is φ = 1040023515984.

The previous prime is 1215221755933. The next prime is 1215221755997. The reversal of 1215221755993 is 3995571225121.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1215221755993 - 2¹³ = 1215221747801 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1215221755993.

It is not an unprimeable number, because it can be changed into a prime (1215221755997) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 132922771 + ... + 132931912.

It is an arithmetic number, because the mean of its divisors is an integer number (173868963336).

Almost surely, 2^{1215221755993} is an apocalyptic number.

It is an amenable number.

1215221755993 is a deficient number, since it is larger than the sum of its proper divisors (175729950695).

1215221755993 is an equidigital number, since it uses as much as digits as its factorization.

1215221755993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 265855343.

The product of its digits is 1701000, while the sum is 52.

The spelling of 1215221755993 in words is "one trillion, two hundred fifteen billion, two hundred twenty-one million, seven hundred fifty-five thousand, nine hundred ninety-three".