66937139 has 4 divisors (see below), whose sum is σ = 67001880. Its totient is φ = 66872400.

The previous prime is 66937121. The next prime is 66937147. The reversal of 66937139 is 93173966.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66937139 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66937139.

It is not an unprimeable number, because it can be changed into a prime (66937159) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30794 + ... + 32895.

It is an arithmetic number, because the mean of its divisors is an integer number (16750470).

Almost surely, 2^66937139 is an apocalyptic number.

66937139 is a deficient number, since it is larger than the sum of its proper divisors (64741).

66937139 is a wasteful number, since it uses less digits than its factorization.

66937139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64740.

The product of its digits is 183708, while the sum is 44.

The square root of 66937139 is about 8181.5120240699. The cubic root of 66937139 is about 406.0277489184.

It can be divided in two parts, 66937 and 139, that added together give a palindrome (67076).

The spelling of 66937139 in words is "sixty-six million, nine hundred thirty-seven thousand, one hundred thirty-nine".