20439331 has 16 divisors (see below), whose sum is σ = 22998528. Its totient is φ = 18007200.

The previous prime is 20439329. The next prime is 20439347. The reversal of 20439331 is 13393402.

It is a happy number.

It is not a de Polignac number, because 20439331 - 2¹ = 20439329 is a prime.

It is a super-2 number, since 2×20439331² = 835532503455122, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20439296 and 20439305.

It is not an unprimeable number, because it can be changed into a prime (20439931) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55510 + ... + 55876.

It is an arithmetic number, because the mean of its divisors is an integer number (1437408).

Almost surely, 2^20439331 is an apocalyptic number.

20439331 is a deficient number, since it is larger than the sum of its proper divisors (2559197).

20439331 is a wasteful number, since it uses less digits than its factorization.

20439331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 522.

The product of its (nonzero) digits is 1944, while the sum is 25.

The square root of 20439331 is about 4520.9878345335. The cubic root of 20439331 is about 273.4149298660.

The spelling of 20439331 in words is "twenty million, four hundred thirty-nine thousand, three hundred thirty-one".