20331520 has 132 divisors (see below), whose sum is σ = 56153304. Its totient is φ = 7004160.

The previous prime is 20331503. The next prime is 20331533. The reversal of 20331520 is 2513302.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a junction number, because it is equal to n+sod(n) for n = 20331494 and 20331503.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1070071 + ... + 1070089.

Almost surely, 2^20331520 is an apocalyptic number.

20331520 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 20331520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28076652).

20331520 is an abundant number, since it is smaller than the sum of its proper divisors (35821784).

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

20331520 is a wasteful number, since it uses less digits than its factorization.

20331520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74 (or 37 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 16.

The square root of 20331520 is about 4509.0486801542. The cubic root of 20331520 is about 272.9333564242.

Adding to 20331520 its reverse (2513302), we get a palindrome (22844822).

It can be divided in two parts, 2033 and 1520, that added together give a palindrome (3553).

The spelling of 20331520 in words is "twenty million, three hundred thirty-one thousand, five hundred twenty".