20151320 has 64 divisors (see below), whose sum is σ = 52531200. Its totient is φ = 6814080.

The previous prime is 20151319. The next prime is 20151349. The reversal of 20151320 is 2315102.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a junction number, because it is equal to n+sod(n) for n = 20151295 and 20151304.

It is a congruent number.

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, 21665 + ... + 22575.

It is an arithmetic number, because the mean of its divisors is an integer number (820800).

Almost surely, 2^20151320 is an apocalyptic number.

20151320 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 20151320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26265600).

20151320 is an abundant number, since it is smaller than the sum of its proper divisors (32379880).

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

20151320 is a wasteful number, since it uses less digits than its factorization.

20151320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1008 (or 1004 counting only the distinct ones).

The product of its (nonzero) digits is 60, while the sum is 14.

The square root of 20151320 is about 4489.0221652382. The cubic root of 20151320 is about 272.1246185021.

Adding to 20151320 its reverse (2315102), we get a palindrome (22466422).

The spelling of 20151320 in words is "twenty million, one hundred fifty-one thousand, three hundred twenty".