20021039 has 4 divisors (see below), whose sum is σ = 20031456. Its totient is φ = 20010624.

The previous prime is 20021021. The next prime is 20021059. The reversal of 20021039 is 93012002.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 20021039 - 2¹² = 20016943 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20021059) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1394 + ... + 6479.

It is an arithmetic number, because the mean of its divisors is an integer number (5007864).

Almost surely, 2^20021039 is an apocalyptic number.

20021039 is a deficient number, since it is larger than the sum of its proper divisors (10417).

20021039 is an equidigital number, since it uses as much as digits as its factorization.

20021039 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10416.

The product of its (nonzero) digits is 108, while the sum is 17.

The square root of 20021039 is about 4474.4875684261. The cubic root of 20021039 is about 271.5369093575.

The spelling of 20021039 in words is "twenty million, twenty-one thousand, thirty-nine".