20811480 has 32 divisors (see below), whose sum is σ = 62434800. Its totient is φ = 5549696.

The previous prime is 20811467. The next prime is 20811487. The reversal of 20811480 is 8411802.

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

It is a self number, because there is not a number n which added to its sum of digits gives 20811480.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20811487) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 86595 + ... + 86834.

Almost surely, 2^20811480 is an apocalyptic number.

20811480 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20811480 is an abundant number, since it is smaller than the sum of its proper divisors (41623320).

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

20811480 is a wasteful number, since it uses less digits than its factorization.

20811480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173443 (or 173439 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 24.

The square root of 20811480 is about 4561.9601050426. The cubic root of 20811480 is about 275.0643595921.

The spelling of 20811480 in words is "twenty million, eight hundred eleven thousand, four hundred eighty".