221215403240 has 128 divisors (see below), whose sum is σ = 577996473600. Its totient is φ = 75493140480.

The previous prime is 221215403191. The next prime is 221215403267. The reversal of 221215403240 is 42304512122.

221215403240 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (26).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 132029 + ... + 678131.

It is an arithmetic number, because the mean of its divisors is an integer number (4515597450).

Almost surely, 2^221215403240 is an apocalyptic number.

221215403240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221215403240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (288998236800).

221215403240 is an abundant number, since it is smaller than the sum of its proper divisors (356781070360).

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

221215403240 is a wasteful number, since it uses less digits than its factorization.

221215403240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 546187 (or 546183 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 26.

Adding to 221215403240 its reverse (42304512122), we get a palindrome (263519915362).

The spelling of 221215403240 in words is "two hundred twenty-one billion, two hundred fifteen million, four hundred three thousand, two hundred forty".