2045931320221 has 4 divisors (see below), whose sum is σ = 2045934971100. Its totient is φ = 2045927669344.

The previous prime is 2045931320171. The next prime is 2045931320267. The reversal of 2045931320221 is 1220231395402.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1240450200025 + 805481120196 = 1113755^2 + 897486^2 .

It is a cyclic number.

It is not a de Polignac number, because 2045931320221 - 2³¹ = 2043783836573 is a prime.

It is a super-2 number, since 2×2045931320221² (a number of 25 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 (2045931320021) 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, 788506 + ... + 2171083.

It is an arithmetic number, because the mean of its divisors is an integer number (511483742775).

Almost surely, 2^{2045931320221} is an apocalyptic number.

It is an amenable number.

2045931320221 is a deficient number, since it is larger than the sum of its proper divisors (3650879).

2045931320221 is an equidigital number, since it uses as much as digits as its factorization.

2045931320221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3650878.

The product of its (nonzero) digits is 25920, while the sum is 34.

The spelling of 2045931320221 in words is "two trillion, forty-five billion, nine hundred thirty-one million, three hundred twenty thousand, two hundred twenty-one".