20115660 has 24 divisors (see below), whose sum is σ = 56324016. Its totient is φ = 5364160.

The previous prime is 20115659. The next prime is 20115713. The reversal of 20115660 is 6651102.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 167571 + ... + 167690.

It is an arithmetic number, because the mean of its divisors is an integer number (2346834).

Almost surely, 2^20115660 is an apocalyptic number.

20115660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20115660 is an abundant number, since it is smaller than the sum of its proper divisors (36208356).

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

20115660 is a wasteful number, since it uses less digits than its factorization.

20115660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 335273 (or 335271 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 21.

The square root of 20115660 is about 4485.0484947211. The cubic root of 20115660 is about 271.9640054734.

Adding to 20115660 its reverse (6651102), we get a palindrome (26766762).

The spelling of 20115660 in words is "twenty million, one hundred fifteen thousand, six hundred sixty".