221421255544541 has 4 divisors (see below), whose sum is σ = 238453659817212. Its totient is φ = 204388851271872.

The previous prime is 221421255544501. The next prime is 221421255544607. The reversal of 221421255544541 is 145445552124122.

221421255544541 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 133132136124100 + 88289119420441 = 11538290^2 + 9396229^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221421255544541 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 (221421255544501) 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, 8516202136316 + ... + 8516202136341.

It is an arithmetic number, because the mean of its divisors is an integer number (59613414954303).

Almost surely, 2^{221421255544541} is an apocalyptic number.

It is an amenable number.

221421255544541 is a deficient number, since it is larger than the sum of its proper divisors (17032404272671).

221421255544541 is a wasteful number, since it uses less digits than its factorization.

221421255544541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17032404272670.

The product of its digits is 2560000, while the sum is 47.

The spelling of 221421255544541 in words is "two hundred twenty-one trillion, four hundred twenty-one billion, two hundred fifty-five million, five hundred forty-four thousand, five hundred forty-one".