9963921 has 16 divisors (see below), whose sum is σ = 15346368. Its totient is φ = 5683200.

The previous prime is 9963913. The next prime is 9963929. The reversal of 9963921 is 1293699.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (9963913) and next prime (9963929).

It is not a de Polignac number, because 9963921 - 2³ = 9963913 is a prime.

9963921 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 9963921.

It is not an unprimeable number, because it can be changed into a prime (9963929) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8320 + ... + 9441.

It is an arithmetic number, because the mean of its divisors is an integer number (959148).

Almost surely, 2^9963921 is an apocalyptic number.

It is an amenable number.

9963921 is a deficient number, since it is larger than the sum of its proper divisors (5382447).

9963921 is a wasteful number, since it uses less digits than its factorization.

9963921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17792.

The product of its digits is 26244, while the sum is 39.

The square root of 9963921 is about 3156.5679146820. The cubic root of 9963921 is about 215.1840572781.

The spelling of 9963921 in words is "nine million, nine hundred sixty-three thousand, nine hundred twenty-one".