220997128 has 64 divisors (see below), whose sum is σ = 464486400. Its totient is φ = 97730880.

The previous prime is 220997071. The next prime is 220997129. The reversal of 220997128 is 821799022.

It is not an unprimeable number, because it can be changed into a prime (220997129) 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, 576825 + ... + 577207.

It is an arithmetic number, because the mean of its divisors is an integer number (7257600).

Almost surely, 2^220997128 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 220997128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (232243200).

220997128 is an abundant number, since it is smaller than the sum of its proper divisors (243489272).

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

220997128 is a wasteful number, since it uses less digits than its factorization.

220997128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 562 (or 558 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 40.

The square root of 220997128 is about 14865.9721511915. The cubic root of 220997128 is about 604.5917405929.

The spelling of 220997128 in words is "two hundred twenty million, nine hundred ninety-seven thousand, one hundred twenty-eight".