21533039 has 12 divisors (see below), whose sum is σ = 23796360. Its totient is φ = 19470000.

The previous prime is 21533011. The next prime is 21533047. The reversal of 21533039 is 93033512.

It is not a de Polignac number, because 21533039 - 2⁸ = 21532783 is a prime.

It is a hoax number, since the sum of its digits (26) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21532999 and 21533017.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21533009) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 30017 + ... + 30725.

It is an arithmetic number, because the mean of its divisors is an integer number (1983030).

Almost surely, 2^21533039 is an apocalyptic number.

21533039 is a deficient number, since it is larger than the sum of its proper divisors (2263321).

21533039 is a wasteful number, since it uses less digits than its factorization.

21533039 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 982 (or 971 counting only the distinct ones).

The product of its (nonzero) digits is 2430, while the sum is 26.

The square root of 21533039 is about 4640.3705670991. The cubic root of 21533039 is about 278.2072493181.

The spelling of 21533039 in words is "twenty-one million, five hundred thirty-three thousand, thirty-nine".