66139635 has 16 divisors (see below), whose sum is σ = 106010784. Its totient is φ = 35212032.

The previous prime is 66139621. The next prime is 66139643. The reversal of 66139635 is 53693166.

It is not a de Polignac number, because 66139635 - 2⁸ = 66139379 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66139593 and 66139602.

It is an unprimeable number.

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, 5599 + ... + 12791.

It is an arithmetic number, because the mean of its divisors is an integer number (6625674).

Almost surely, 2^66139635 is an apocalyptic number.

66139635 is a deficient number, since it is larger than the sum of its proper divisors (39871149).

66139635 is a wasteful number, since it uses less digits than its factorization.

66139635 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7814.

The product of its digits is 87480, while the sum is 39.

The square root of 66139635 is about 8132.6278040987. The cubic root of 66139635 is about 404.4088005767.

The spelling of 66139635 in words is "sixty-six million, one hundred thirty-nine thousand, six hundred thirty-five".