20455445221 has 4 divisors (see below), whose sum is σ = 20455740000. Its totient is φ = 20455150444.

The previous prime is 20455445189. The next prime is 20455445237. The reversal of 20455445221 is 12254455402.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 20455445221 - 2⁵ = 20455445189 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20455445281) 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, 20280 + ... + 203278.

It is an arithmetic number, because the mean of its divisors is an integer number (5113935000).

Almost surely, 2^20455445221 is an apocalyptic number.

It is an amenable number.

20455445221 is a deficient number, since it is larger than the sum of its proper divisors (294779).

20455445221 is a wasteful number, since it uses less digits than its factorization.

20455445221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 294778.

The product of its (nonzero) digits is 64000, while the sum is 34.

The spelling of 20455445221 in words is "twenty billion, four hundred fifty-five million, four hundred forty-five thousand, two hundred twenty-one".