65999994 has 16 divisors (see below), whose sum is σ = 132265440. Its totient is φ = 21955760.

The previous prime is 65999993. The next prime is 66000007. The reversal of 65999994 is 49999956.

It is not an unprimeable number, because it can be changed into a prime (65999993) 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, 7752 + ... + 13859.

It is an arithmetic number, because the mean of its divisors is an integer number (8266590).

Almost surely, 2^65999994 is an apocalyptic number.

65999994 is an abundant number, since it is smaller than the sum of its proper divisors (66265446).

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

65999994 is a wasteful number, since it uses less digits than its factorization.

65999994 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22125.

The product of its digits is 7085880, while the sum is 60.

The square root of 65999994 is about 8124.0380353615. The cubic root of 65999994 is about 404.1239898160.

The spelling of 65999994 in words is "sixty-five million, nine hundred ninety-nine thousand, nine hundred ninety-four".