20315320 has 16 divisors (see below), whose sum is σ = 45709560. Its totient is φ = 8126112.

The previous prime is 20315303. The next prime is 20315359. The reversal of 20315320 is 2351302.

It is a junction number, because it is equal to n+sod(n) for n = 20315294 and 20315303.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 253902 + ... + 253981.

Almost surely, 2^20315320 is an apocalyptic number.

20315320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20315320 is an abundant number, since it is smaller than the sum of its proper divisors (25394240).

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

20315320 is a wasteful number, since it uses less digits than its factorization.

20315320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 507894 (or 507890 counting only the distinct ones).

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

The square root of 20315320 is about 4507.2519343831. The cubic root of 20315320 is about 272.8608467571.

Adding to 20315320 its reverse (2351302), we get a palindrome (22666622).

The spelling of 20315320 in words is "twenty million, three hundred fifteen thousand, three hundred twenty".