921271680 has 384 divisors, whose sum is σ = 3697312320. Its totient is φ = 207028224.

The previous prime is 921271669. The next prime is 921271721. The reversal of 921271680 is 86172129.

It is a tau number, because it is divible by the number of its divisors (384).

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 47 ways as a sum of consecutive naturals, for example, 2943204 + ... + 2943516.

Almost surely, 2^921271680 is an apocalyptic number.

921271680 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 921271680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1848656160).

921271680 is an abundant number, since it is smaller than the sum of its proper divisors (2776040640).

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

921271680 is a wasteful number, since it uses less digits than its factorization.

921271680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 418 (or 403 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 36.

The square root of 921271680 is about 30352.4575611267. The cubic root of 921271680 is about 973.0367437281.

The spelling of 921271680 in words is "nine hundred twenty-one million, two hundred seventy-one thousand, six hundred eighty".