66997028 has 12 divisors (see below), whose sum is σ = 133994112. Its totient is φ = 28713000.

The previous prime is 66997013. The next prime is 66997031. The reversal of 66997028 is 82079966.

66997028 is an admirable number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1196348 + ... + 1196403.

It is an arithmetic number, because the mean of its divisors is an integer number (11166176).

Almost surely, 2^66997028 is an apocalyptic number.

It is an amenable number.

66997028 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

66997028 is a wasteful number, since it uses less digits than its factorization.

66997028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2392762 (or 2392760 counting only the distinct ones).

The product of its (nonzero) digits is 326592, while the sum is 47.

The square root of 66997028 is about 8185.1712260649. The cubic root of 66997028 is about 406.1488045225.

The spelling of 66997028 in words is "sixty-six million, nine hundred ninety-seven thousand, twenty-eight".