921166560 has 384 divisors, whose sum is σ = 3437199360. Its totient is φ = 229920768.

The previous prime is 921166549. The next prime is 921166637. The reversal of 921166560 is 65661129.

921166560 is a `hidden beast` number, since 92 + 1 + 1 + 6 + 6 + 560 = 666.

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

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 7253217 + ... + 7253343.

It is an arithmetic number, because the mean of its divisors is an integer number (8951040).

Almost surely, 2^921166560 is an apocalyptic number.

921166560 is a gapful number since it is divisible by the number (90) 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 921166560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1718599680).

921166560 is an abundant number, since it is smaller than the sum of its proper divisors (2516032800).

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

921166560 is a wasteful number, since it uses less digits than its factorization.

921166560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 247 (or 233 counting only the distinct ones).

The product of its (nonzero) digits is 19440, while the sum is 36.

The square root of 921166560 is about 30350.7258562295. The cubic root of 921166560 is about 972.9997334682. Note that the first 3 decimals are identical.

The spelling of 921166560 in words is "nine hundred twenty-one million, one hundred sixty-six thousand, five hundred sixty".