66590020 has 96 divisors (see below), whose sum is σ = 172972800. Its totient is φ = 21450240.

The previous prime is 66590009. The next prime is 66590033. The reversal of 66590020 is 2009566.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 116335 + ... + 116905.

It is an arithmetic number, because the mean of its divisors is an integer number (1801800).

Almost surely, 2^66590020 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66590020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86486400).

66590020 is an abundant number, since it is smaller than the sum of its proper divisors (106382780).

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

66590020 is a wasteful number, since it uses less digits than its factorization.

66590020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 618 (or 602 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 28.

The square root of 66590020 is about 8160.2708288390. The cubic root of 66590020 is about 405.3246799452.

Adding to 66590020 its reverse (2009566), we get a palindrome (68599586).

The spelling of 66590020 in words is "sixty-six million, five hundred ninety thousand, twenty".