66990828 has 12 divisors (see below), whose sum is σ = 156311960. Its totient is φ = 22330272.

The previous prime is 66990823. The next prime is 66990851. The reversal of 66990828 is 82809966.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×66990828² = 8975542072251168, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66990823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2791273 + ... + 2791296.

Almost surely, 2^66990828 is an apocalyptic number.

It is an amenable number.

66990828 is an abundant number, since it is smaller than the sum of its proper divisors (89321132).

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

66990828 is a wasteful number, since it uses less digits than its factorization.

66990828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5582576 (or 5582574 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 48.

The square root of 66990828 is about 8184.7924836247. The cubic root of 66990828 is about 406.1362756072.

The spelling of 66990828 in words is "sixty-six million, nine hundred ninety thousand, eight hundred twenty-eight".