221220506057 has 4 divisors (see below), whose sum is σ = 221234577360. Its totient is φ = 221206434756.

The previous prime is 221220506047. The next prime is 221220506069. The reversal of 221220506057 is 750605022122.

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 not a de Polignac number, because 221220506057 - 2⁶ = 221220505993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221220506047) 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, 7012043 + ... + 7043520.

It is an arithmetic number, because the mean of its divisors is an integer number (55308644340).

Almost surely, 2^221220506057 is an apocalyptic number.

It is an amenable number.

221220506057 is a deficient number, since it is larger than the sum of its proper divisors (14071303).

221220506057 is a wasteful number, since it uses less digits than its factorization.

221220506057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14071302.

The product of its (nonzero) digits is 16800, while the sum is 32.

Adding to 221220506057 its reverse (750605022122), we get a palindrome (971825528179).

The spelling of 221220506057 in words is "two hundred twenty-one billion, two hundred twenty million, five hundred six thousand, fifty-seven".