20319660 has 144 divisors (see below), whose sum is σ = 66227616. Its totient is φ = 5225472.

The previous prime is 20319631. The next prime is 20319667. The reversal of 20319660 is 6691302.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (20319667) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 179764 + ... + 179876.

It is an arithmetic number, because the mean of its divisors is an integer number (459914).

Almost surely, 2^20319660 is an apocalyptic number.

20319660 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 20319660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33113808).

20319660 is an abundant number, since it is smaller than the sum of its proper divisors (45907956).

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

20319660 is a wasteful number, since it uses less digits than its factorization.

20319660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 174 (or 160 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 27.

The square root of 20319660 is about 4507.7333550245. The cubic root of 20319660 is about 272.8802759655.

The spelling of 20319660 in words is "twenty million, three hundred nineteen thousand, six hundred sixty".