20613520 has 80 divisors (see below), whose sum is σ = 53032320. Its totient is φ = 7411712.

The previous prime is 20613491. The next prime is 20613533. The reversal of 20613520 is 2531602.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 30951 + ... + 31609.

It is an arithmetic number, because the mean of its divisors is an integer number (662904).

Almost surely, 2^20613520 is an apocalyptic number.

20613520 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 20613520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26516160).

20613520 is an abundant number, since it is smaller than the sum of its proper divisors (32418800).

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

20613520 is a wasteful number, since it uses less digits than its factorization.

20613520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 712 (or 706 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 19.

The square root of 20613520 is about 4540.2114488204. The cubic root of 20613520 is about 274.1894369023.

The spelling of 20613520 in words is "twenty million, six hundred thirteen thousand, five hundred twenty".