491120121021221 has 4 divisors (see below), whose sum is σ = 491211970684512. Its totient is φ = 491028271357932.

The previous prime is 491120121021193. The next prime is 491120121021247. The reversal of 491120121021221 is 122120121021194.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-491120121021221 is a prime.

It is a super-2 number, since 2×491120121021221² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (491120121021281) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45924823625 + ... + 45924834318.

It is an arithmetic number, because the mean of its divisors is an integer number (122802992671128).

Almost surely, 2^{491120121021221} is an apocalyptic number.

It is an amenable number.

491120121021221 is a deficient number, since it is larger than the sum of its proper divisors (91849663291).

491120121021221 is an equidigital number, since it uses as much as digits as its factorization.

491120121021221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91849663290.

The product of its (nonzero) digits is 1152, while the sum is 29.

The spelling of 491120121021221 in words is "four hundred ninety-one trillion, one hundred twenty billion, one hundred twenty-one million, twenty-one thousand, two hundred twenty-one".