66658998 has 32 divisors (see below), whose sum is σ = 153575424. Its totient is φ = 18893952.

The previous prime is 66658997. The next prime is 66659003. The reversal of 66658998 is 89985666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66658993) 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, 915 + ... + 11582.

It is an arithmetic number, because the mean of its divisors is an integer number (4799232).

Almost surely, 2^66658998 is an apocalyptic number.

66658998 is an abundant number, since it is smaller than the sum of its proper divisors (86916426).

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

66658998 is a wasteful number, since it uses less digits than its factorization.

66658998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12636.

The product of its digits is 5598720, while the sum is 57.

The square root of 66658998 is about 8164.4961877632. The cubic root of 66658998 is about 405.4645849821.

The spelling of 66658998 in words is "sixty-six million, six hundred fifty-eight thousand, nine hundred ninety-eight".