221345431555 has 16 divisors (see below), whose sum is σ = 267179328000. Its totient is φ = 176034349440.

The previous prime is 221345431511. The next prime is 221345431609. The reversal of 221345431555 is 555134543122.

It is not a de Polignac number, because 221345431555 - 2¹¹ = 221345429507 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1404481 + ... + 1554109.

It is an arithmetic number, because the mean of its divisors is an integer number (16698708000).

Almost surely, 2^221345431555 is an apocalyptic number.

221345431555 is a deficient number, since it is larger than the sum of its proper divisors (45833896445).

221345431555 is a wasteful number, since it uses less digits than its factorization.

221345431555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 151374.

The product of its digits is 360000, while the sum is 40.

Adding to 221345431555 its reverse (555134543122), we get a palindrome (776479974677).

The spelling of 221345431555 in words is "two hundred twenty-one billion, three hundred forty-five million, four hundred thirty-one thousand, five hundred fifty-five".