221401320 has 64 divisors (see below), whose sum is σ = 759093120. Its totient is φ = 50605824.

The previous prime is 221401291. The next prime is 221401321. The reversal of 221401320 is 23104122.

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

It is a self number, because there is not a number n which added to its sum of digits gives 221401320.

It is not an unprimeable number, because it can be changed into a prime (221401321) 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, 130947 + ... + 132626.

It is an arithmetic number, because the mean of its divisors is an integer number (11860830).

Almost surely, 2^221401320 is an apocalyptic number.

221401320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221401320 is an abundant number, since it is smaller than the sum of its proper divisors (537691800).

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

221401320 is a wasteful number, since it uses less digits than its factorization.

221401320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 263594 (or 263590 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 221401320 is about 14879.5604773797. The cubic root of 221401320 is about 604.9601048301.

Adding to 221401320 its reverse (23104122), we get a palindrome (244505442).

The spelling of 221401320 in words is "two hundred twenty-one million, four hundred one thousand, three hundred twenty".