221479920 has 120 divisors (see below), whose sum is σ = 771419376. Its totient is φ = 59056128.

The previous prime is 221479913. The next prime is 221479967. The reversal of 221479920 is 29974122.

221479920 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 (120).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 13744 + ... + 25136.

Almost surely, 2^221479920 is an apocalyptic number.

221479920 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 221479920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (385709688).

221479920 is an abundant number, since it is smaller than the sum of its proper divisors (549939456).

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

221479920 is a wasteful number, since it uses less digits than its factorization.

221479920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11421 (or 11403 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 221479920 is about 14882.2014500544. The cubic root of 221479920 is about 605.0316856114.

The spelling of 221479920 in words is "two hundred twenty-one million, four hundred seventy-nine thousand, nine hundred twenty".