20669439 has 32 divisors (see below), whose sum is σ = 32488960. Its totient is φ = 11446272.

The previous prime is 20669413. The next prime is 20669443. The reversal of 20669439 is 93496602.

It is a happy number.

It is not a de Polignac number, because 20669439 - 2⁸ = 20669183 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20669397 and 20669406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20669459) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 148632 + ... + 148770.

It is an arithmetic number, because the mean of its divisors is an integer number (1015280).

Almost surely, 2^20669439 is an apocalyptic number.

20669439 is a deficient number, since it is larger than the sum of its proper divisors (11819521).

20669439 is a wasteful number, since it uses less digits than its factorization.

20669439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 319.

The product of its (nonzero) digits is 69984, while the sum is 39.

The square root of 20669439 is about 4546.3654714508. The cubic root of 20669439 is about 274.4371473974.

The spelling of 20669439 in words is "twenty million, six hundred sixty-nine thousand, four hundred thirty-nine".