921424 has 40 divisors (see below), whose sum is σ = 2152640. Its totient is φ = 373248.

The previous prime is 921409. The next prime is 921457. The reversal of 921424 is 424129.

It is a junction number, because it is equal to n+sod(n) for n = 921395 and 921404.

It is a congruent number.

It is an unprimeable number.

921424 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1912 + ... + 2344.

It is an arithmetic number, because the mean of its divisors is an integer number (53816).

2⁹²¹⁴²⁴ 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 921424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1076320).

921424 is an abundant number, since it is smaller than the sum of its proper divisors (1231216).

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

921424 is a wasteful number, since it uses less digits than its factorization.

921424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 467 (or 461 counting only the distinct ones).

The product of its digits is 576, while the sum is 22.

The square root of 921424 is about 959.9083289565. The cubic root of 921424 is about 97.3090366994.

The spelling of 921424 in words is "nine hundred twenty-one thousand, four hundred twenty-four".