20814720 has 128 divisors (see below), whose sum is σ = 68372640. Its totient is φ = 5382144.

The previous prime is 20814719. The next prime is 20814727. The reversal of 20814720 is 2741802.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20814727) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 70894 + ... + 71186.

Almost surely, 2^20814720 is an apocalyptic number.

20814720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20814720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34186320).

20814720 is an abundant number, since it is smaller than the sum of its proper divisors (47557920).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20814720 is a wasteful number, since it uses less digits than its factorization.

20814720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 352 (or 340 counting only the distinct ones).

The product of its (nonzero) digits is 896, while the sum is 24.

The square root of 20814720 is about 4562.3152017369. The cubic root of 20814720 is about 275.0786331610.

The spelling of 20814720 in words is "twenty million, eight hundred fourteen thousand, seven hundred twenty".