20535660 has 96 divisors (see below), whose sum is σ = 67677120. Its totient is φ = 5151744.

The previous prime is 20535659. The next prime is 20535661. The reversal of 20535660 is 6653502.

It is an interprime number because it is at equal distance from previous prime (20535659) and next prime (20535661).

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 (20535661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8062 + ... + 10298.

It is an arithmetic number, because the mean of its divisors is an integer number (704970).

Almost surely, 2^20535660 is an apocalyptic number.

20535660 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 20535660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33838560).

20535660 is an abundant number, since it is smaller than the sum of its proper divisors (47141460).

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

20535660 is a wasteful number, since it uses less digits than its factorization.

20535660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2272 (or 2264 counting only the distinct ones).

The product of its (nonzero) digits is 5400, while the sum is 27.

The square root of 20535660 is about 4531.6288462318. The cubic root of 20535660 is about 273.8437847176.

The spelling of 20535660 in words is "twenty million, five hundred thirty-five thousand, six hundred sixty".