20336421 has 24 divisors (see below), whose sum is σ = 32403360. Its totient is φ = 11303712.

The previous prime is 20336419. The next prime is 20336429. The reversal of 20336421 is 12463302.

It is a happy number.

It is not a de Polignac number, because 20336421 - 2¹ = 20336419 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20336429) 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 23 ways as a sum of consecutive naturals, for example, 3570 + ... + 7308.

It is an arithmetic number, because the mean of its divisors is an integer number (1350140).

Almost surely, 2^20336421 is an apocalyptic number.

20336421 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20336421 is a deficient number, since it is larger than the sum of its proper divisors (12066939).

20336421 is a wasteful number, since it uses less digits than its factorization.

20336421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3793 (or 3786 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 21.

The square root of 20336421 is about 4509.5921101581. The cubic root of 20336421 is about 272.9552852472.

Adding to 20336421 its reverse (12463302), we get a palindrome (32799723).

The spelling of 20336421 in words is "twenty million, three hundred thirty-six thousand, four hundred twenty-one".