221401024 has 56 divisors (see below), whose sum is σ = 475323408. Its totient is φ = 101713920.

The previous prime is 221401009. The next prime is 221401049. The reversal of 221401024 is 420104122.

221401024 is digitally balanced in base 3, 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 (16).

It is a junction number, because it is equal to n+sod(n) for n = 221400989 and 221401007.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 233319 + ... + 234265.

It is an arithmetic number, because the mean of its divisors is an integer number (8487918).

Almost surely, 2^221401024 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221401024, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (237661704).

221401024 is an abundant number, since it is smaller than the sum of its proper divisors (253922384).

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

221401024 is a wasteful number, since it uses less digits than its factorization.

221401024 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1253 (or 1243 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

The square root of 221401024 is about 14879.5505308460. The cubic root of 221401024 is about 604.9598352317.

Adding to 221401024 its reverse (420104122), we get a palindrome (641505146).

The spelling of 221401024 in words is "two hundred twenty-one million, four hundred one thousand, twenty-four".