221040240 has 40 divisors (see below), whose sum is σ = 685225488. Its totient is φ = 58944000.

The previous prime is 221040229. The next prime is 221040241. The reversal of 221040240 is 42040122.

221040240 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221040241) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 460261 + ... + 460740.

Almost surely, 2^221040240 is an apocalyptic number.

221040240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221040240 is an abundant number, since it is smaller than the sum of its proper divisors (464185248).

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

221040240 is a wasteful number, since it uses less digits than its factorization.

221040240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 921017 (or 921011 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 15.

The square root of 221040240 is about 14867.4221033776. The cubic root of 221040240 is about 604.6310525131.

Adding to 221040240 its reverse (42040122), we get a palindrome (263080362).

The spelling of 221040240 in words is "two hundred twenty-one million, forty thousand, two hundred forty".