20457824 has 12 divisors (see below), whose sum is σ = 40276404. Its totient is φ = 10228896.

The previous prime is 20457823. The next prime is 20457863. The reversal of 20457824 is 42875402.

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: 639307 = 20457824 / (2 + 0 + 4 + 5 + 7 + 8 + 2 + 4).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20457821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319622 + ... + 319685.

It is an arithmetic number, because the mean of its divisors is an integer number (3356367).

Almost surely, 2^20457824 is an apocalyptic number.

It is an amenable number.

20457824 is a deficient number, since it is larger than the sum of its proper divisors (19818580).

20457824 is an equidigital number, since it uses as much as digits as its factorization.

20457824 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 639317 (or 639309 counting only the distinct ones).

The product of its (nonzero) digits is 17920, while the sum is 32.

The square root of 20457824 is about 4523.0326109813. The cubic root of 20457824 is about 273.4973646929.

The spelling of 20457824 in words is "twenty million, four hundred fifty-seven thousand, eight hundred twenty-four".