21264328 has 32 divisors (see below), whose sum is σ = 41918400. Its totient is φ = 10093248.

The previous prime is 21264323. The next prime is 21264349. The reversal of 21264328 is 82346212.

It is a super-3 number, since 3×21264328³ (a number of 23 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21264296 and 21264305.

It is not an unprimeable number, because it can be changed into a prime (21264323) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29638 + ... + 30346.

It is an arithmetic number, because the mean of its divisors is an integer number (1309950).

Almost surely, 2^21264328 is an apocalyptic number.

It is an amenable number.

21264328 is a deficient number, since it is larger than the sum of its proper divisors (20654072).

21264328 is a wasteful number, since it uses less digits than its factorization.

21264328 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 901 (or 897 counting only the distinct ones).

The product of its digits is 4608, while the sum is 28.

The square root of 21264328 is about 4611.3260565698. The cubic root of 21264328 is about 277.0451515758.

The spelling of 21264328 in words is "twenty-one million, two hundred sixty-four thousand, three hundred twenty-eight".