66004420 has 24 divisors (see below), whose sum is σ = 138965400. Its totient is φ = 26333952.

The previous prime is 66004399. The next prime is 66004453. The reversal of 66004420 is 2440066.

It can be written as a sum of positive squares in 4 ways, for example, as 2515396 + 63489024 = 1586^2 + 7968^2 .

It is a junction number, because it is equal to n+sod(n) for n = 66004391 and 66004400.

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, 4146 + ... + 12214.

It is an arithmetic number, because the mean of its divisors is an integer number (5790225).

Almost surely, 2^66004420 is an apocalyptic number.

It is an amenable number.

66004420 is an abundant number, since it is smaller than the sum of its proper divisors (72960980).

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

66004420 is a wasteful number, since it uses less digits than its factorization.

66004420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8487 (or 8485 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 22.

The square root of 66004420 is about 8124.3104322767. The cubic root of 66004420 is about 404.1330232148.

Adding to 66004420 its reverse (2440066), we get a palindrome (68444486).

The spelling of 66004420 in words is "sixty-six million, four thousand, four hundred twenty".