921663 has 6 divisors (see below), whose sum is σ = 1331304. Its totient is φ = 614436.

The previous prime is 921647. The next prime is 921667. The reversal of 921663 is 366129.

It is a happy number.

921663 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 921663 - 2⁴ = 921647 is a prime.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 921663.

It is not an unprimeable number, because it can be changed into a prime (921667) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 51195 + ... + 51212.

It is an arithmetic number, because the mean of its divisors is an integer number (221884).

2⁹²¹⁶⁶³ is an apocalyptic number.

921663 is a deficient number, since it is larger than the sum of its proper divisors (409641).

921663 is a wasteful number, since it uses less digits than its factorization.

921663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102413 (or 102410 counting only the distinct ones).

The product of its digits is 1944, while the sum is 27.

The square root of 921663 is about 960.0328119393. The cubic root of 921663 is about 97.3174493481.

The spelling of 921663 in words is "nine hundred twenty-one thousand, six hundred sixty-three".