20434784 has 12 divisors (see below), whose sum is σ = 40231044. Its totient is φ = 10217376.

The previous prime is 20434759. The next prime is 20434789. The reversal of 20434784 is 48743402.

It is a Harshad number since it is a multiple of its sum of digits (32), and also a Moran number because the ratio is a prime number: 638587 = 20434784 / (2 + 0 + 4 + 3 + 4 + 7 + 8 + 4).

It is a self number, because there is not a number n which added to its sum of digits gives 20434784.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20434789) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319262 + ... + 319325.

It is an arithmetic number, because the mean of its divisors is an integer number (3352587).

Almost surely, 2^20434784 is an apocalyptic number.

It is an amenable number.

20434784 is a deficient number, since it is larger than the sum of its proper divisors (19796260).

20434784 is an equidigital number, since it uses as much as digits as its factorization.

20434784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 638597 (or 638589 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 32.

The square root of 20434784 is about 4520.4849297393. The cubic root of 20434784 is about 273.3946534378.

The spelling of 20434784 in words is "twenty million, four hundred thirty-four thousand, seven hundred eighty-four".