66838820 has 48 divisors (see below), whose sum is σ = 143434368. Its totient is φ = 26158080.

The previous prime is 66838817. The next prime is 66838843. The reversal of 66838820 is 2883866.

It is a Smith number, since the sum of its digits (41) coincides with the sum of the digits of its prime factors.

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, 254009 + ... + 254271.

It is an arithmetic number, because the mean of its divisors is an integer number (2988216).

Almost surely, 2^66838820 is an apocalyptic number.

It is an amenable number.

66838820 is an abundant number, since it is smaller than the sum of its proper divisors (76595548).

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

66838820 is a wasteful number, since it uses less digits than its factorization.

66838820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 500 (or 498 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 41.

The square root of 66838820 is about 8175.5012078771. The cubic root of 66838820 is about 405.8288568230.

The spelling of 66838820 in words is "sixty-six million, eight hundred thirty-eight thousand, eight hundred twenty".