921018 has 16 divisors (see below), whose sum is σ = 2105280. Its totient is φ = 263136.

The previous prime is 921013. The next prime is 921029. The reversal of 921018 is 810129.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an alternating number because its digits alternate between odd and even.

It is a junction number, because it is equal to n+sod(n) for n = 920985 and 921003.

It is not an unprimeable number, because it can be changed into a prime (921013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10923 + ... + 11006.

It is an arithmetic number, because the mean of its divisors is an integer number (131580).

2⁹²¹⁰¹⁸ is an apocalyptic number.

921018 is an abundant number, since it is smaller than the sum of its proper divisors (1184262).

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

921018 is a wasteful number, since it uses less digits than its factorization.

921018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21941.

The product of its (nonzero) digits is 144, while the sum is 21.

The square root of 921018 is about 959.6968271282. The cubic root of 921018 is about 97.2947424212.

Subtracting from 921018 its reverse (810129), we obtain a square (110889 = 333²).

The spelling of 921018 in words is "nine hundred twenty-one thousand, eighteen".