66981039 has 16 divisors (see below), whose sum is σ = 93774720. Its totient is φ = 42467040.

The previous prime is 66981017. The next prime is 66981053. The reversal of 66981039 is 93018966.

It is not a de Polignac number, because 66981039 - 2⁵ = 66981007 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66981059) 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 15 ways as a sum of consecutive naturals, for example, 84 + ... + 11574.

It is an arithmetic number, because the mean of its divisors is an integer number (5860920).

Almost surely, 2^66981039 is an apocalyptic number.

66981039 is a deficient number, since it is larger than the sum of its proper divisors (26793681).

66981039 is a wasteful number, since it uses less digits than its factorization.

66981039 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11590.

The product of its (nonzero) digits is 69984, while the sum is 42.

The square root of 66981039 is about 8184.1944624990. The cubic root of 66981039 is about 406.1164924926.

The spelling of 66981039 in words is "sixty-six million, nine hundred eighty-one thousand, thirty-nine".