65991938 has 16 divisors (see below), whose sum is σ = 99963936. Its totient is φ = 32672640.

The previous prime is 65991931. The next prime is 65991949. The reversal of 65991938 is 83919956.

It is not an unprimeable number, because it can be changed into a prime (65991931) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 148745 + ... + 149187.

It is an arithmetic number, because the mean of its divisors is an integer number (6247746).

Almost surely, 2^65991938 is an apocalyptic number.

65991938 is a deficient number, since it is larger than the sum of its proper divisors (33971998).

65991938 is a wasteful number, since it uses less digits than its factorization.

65991938 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1009.

The product of its digits is 524880, while the sum is 50.

The square root of 65991938 is about 8123.5422076826. The cubic root of 65991938 is about 404.1075466058.

The spelling of 65991938 in words is "sixty-five million, nine hundred ninety-one thousand, nine hundred thirty-eight".