66699438 has 32 divisors (see below), whose sum is σ = 145815936. Its totient is φ = 20215008.

The previous prime is 66699433. The next prime is 66699461. The reversal of 66699438 is 83499666.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66699433) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1156 + ... + 11607.

It is an arithmetic number, because the mean of its divisors is an integer number (4556748).

Almost surely, 2^66699438 is an apocalyptic number.

66699438 is an abundant number, since it is smaller than the sum of its proper divisors (79116498).

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

66699438 is a wasteful number, since it uses less digits than its factorization.

66699438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12848.

The product of its digits is 1679616, while the sum is 51.

The square root of 66699438 is about 8166.9723888354. The cubic root of 66699438 is about 405.5465627775.

The spelling of 66699438 in words is "sixty-six million, six hundred ninety-nine thousand, four hundred thirty-eight".