215440380001721 has 32 divisors (see below), whose sum is σ = 269863648704000. Its totient is φ = 167699874972672.

The previous prime is 215440380001657. The next prime is 215440380001723. The reversal of 215440380001721 is 127100083044512.

It is a happy number.

It is not a de Polignac number, because 215440380001721 - 2⁶ = 215440380001657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (215440380001723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 14641826 + ... + 25402043.

It is an arithmetic number, because the mean of its divisors is an integer number (8433239022000).

Almost surely, 2^{215440380001721} is an apocalyptic number.

It is an amenable number.

215440380001721 is a deficient number, since it is larger than the sum of its proper divisors (54423268702279).

215440380001721 is a wasteful number, since it uses less digits than its factorization.

215440380001721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40045481.

The product of its (nonzero) digits is 53760, while the sum is 38.

The spelling of 215440380001721 in words is "two hundred fifteen trillion, four hundred forty billion, three hundred eighty million, one thousand, seven hundred twenty-one".