66985428 has 24 divisors (see below), whose sum is σ = 159249888. Its totient is φ = 21906976.

The previous prime is 66985421. The next prime is 66985433. The reversal of 66985428 is 82458966.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66985421) 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 7 ways as a sum of consecutive naturals, for example, 52026 + ... + 53297.

It is an arithmetic number, because the mean of its divisors is an integer number (6635412).

Almost surely, 2^66985428 is an apocalyptic number.

It is an amenable number.

66985428 is an abundant number, since it is smaller than the sum of its proper divisors (92264460).

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

66985428 is a wasteful number, since it uses less digits than its factorization.

66985428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105383 (or 105381 counting only the distinct ones).

The product of its digits is 829440, while the sum is 48.

The square root of 66985428 is about 8184.4625968966. The cubic root of 66985428 is about 406.1253626962.

The spelling of 66985428 in words is "sixty-six million, nine hundred eighty-five thousand, four hundred twenty-eight".