66039998 has 16 divisors (see below), whose sum is σ = 101122560. Its totient is φ = 32336856.

The previous prime is 66039997. The next prime is 66040033. The reversal of 66039998 is 89993066.

It is a super-2 number, since 2×66039998² = 8722562671680008, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66039997) 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, 35315 + ... + 37137.

It is an arithmetic number, because the mean of its divisors is an integer number (6320160).

Almost surely, 2^66039998 is an apocalyptic number.

66039998 is a deficient number, since it is larger than the sum of its proper divisors (35082562).

66039998 is a wasteful number, since it uses less digits than its factorization.

66039998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2191.

The product of its (nonzero) digits is 629856, while the sum is 50.

The square root of 66039998 is about 8126.4997385098. The cubic root of 66039998 is about 404.2056227067.

The spelling of 66039998 in words is "sixty-six million, thirty-nine thousand, nine hundred ninety-eight".