921128560 has 80 divisors (see below), whose sum is σ = 2386132992. Its totient is φ = 327814400.

The previous prime is 921128557. The next prime is 921128597. The reversal of 921128560 is 65821129.

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

It is a hoax number, since the sum of its digits (34) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 30225 + ... + 52495.

Almost surely, 2^921128560 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 921128560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1193066496).

921128560 is an abundant number, since it is smaller than the sum of its proper divisors (1465004432).

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

921128560 is a wasteful number, since it uses less digits than its factorization.

921128560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22342 (or 22336 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 34.

The square root of 921128560 is about 30350.0998350912. The cubic root of 921128560 is about 972.9863538761.

Adding to 921128560 its reverse (65821129), we get a palindrome (986949689).

The spelling of 921128560 in words is "nine hundred twenty-one million, one hundred twenty-eight thousand, five hundred sixty".