221856079440 has 80 divisors (see below), whose sum is σ = 723951432000. Its totient is φ = 56047850496.

The previous prime is 221856079433. The next prime is 221856079441. The reversal of 221856079440 is 44970658122.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 221856079440.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221856079441) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24321765 + ... + 24330884.

It is an arithmetic number, because the mean of its divisors is an integer number (9049392900).

Almost surely, 2^221856079440 is an apocalyptic number.

221856079440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221856079440 is an abundant number, since it is smaller than the sum of its proper divisors (502095352560).

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

221856079440 is a wasteful number, since it uses less digits than its factorization.

221856079440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48652684 (or 48652678 counting only the distinct ones).

The product of its (nonzero) digits is 967680, while the sum is 48.

The spelling of 221856079440 in words is "two hundred twenty-one billion, eight hundred fifty-six million, seventy-nine thousand, four hundred forty".