221543404240 has 20 divisors (see below), whose sum is σ = 515088415044. Its totient is φ = 88617361664.

The previous prime is 221543404219. The next prime is 221543404241. The reversal of 221543404240 is 42404345122.

It can be written as a sum of positive squares in 2 ways, for example, as 107431861824 + 114111542416 = 327768^2 + 337804^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221543404241) 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, 1384646197 + ... + 1384646356.

Almost surely, 2^221543404240 is an apocalyptic number.

221543404240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221543404240 is an abundant number, since it is smaller than the sum of its proper divisors (293545010804).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221543404240 is a wasteful number, since it uses less digits than its factorization.

221543404240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2769292566 (or 2769292560 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 31.

Adding to 221543404240 its reverse (42404345122), we get a palindrome (263947749362).

The spelling of 221543404240 in words is "two hundred twenty-one billion, five hundred forty-three million, four hundred four thousand, two hundred forty".