221534055631447 has 4 divisors (see below), whose sum is σ = 238575136833880. Its totient is φ = 204492974429016.

The previous prime is 221534055631391. The next prime is 221534055631477. The reversal of 221534055631447 is 744136550435122.

It is a happy number.

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

It is not a de Polignac number, because 221534055631447 - 2¹⁹ = 221534055107159 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221534055631394 and 221534055631403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221534055631477) 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, 8520540601197 + ... + 8520540601222.

It is an arithmetic number, because the mean of its divisors is an integer number (59643784208470).

Almost surely, 2^{221534055631447} is an apocalyptic number.

221534055631447 is a deficient number, since it is larger than the sum of its proper divisors (17041081202433).

221534055631447 is a wasteful number, since it uses less digits than its factorization.

221534055631447 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17041081202432.

The product of its (nonzero) digits is 12096000, while the sum is 52.

The spelling of 221534055631447 in words is "two hundred twenty-one trillion, five hundred thirty-four billion, fifty-five million, six hundred thirty-one thousand, four hundred forty-seven".