221840538505 has 8 divisors (see below), whose sum is σ = 266247476352. Its totient is φ = 177446544048.

The previous prime is 221840538499. The next prime is 221840538509. The reversal of 221840538505 is 505835048122.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 221840538505 - 2¹⁵ = 221840505737 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221840538509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3198099 + ... + 3266728.

It is an arithmetic number, because the mean of its divisors is an integer number (33280934544).

Almost surely, 2^221840538505 is an apocalyptic number.

It is an amenable number.

221840538505 is a deficient number, since it is larger than the sum of its proper divisors (44406937847).

221840538505 is an equidigital number, since it uses as much as digits as its factorization.

221840538505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6471695.

The product of its (nonzero) digits is 384000, while the sum is 43.

The spelling of 221840538505 in words is "two hundred twenty-one billion, eight hundred forty million, five hundred thirty-eight thousand, five hundred five".