66554990 has 16 divisors (see below), whose sum is σ = 119927952. Its totient is φ = 26593344.

The previous prime is 66554987. The next prime is 66555023. The reversal of 66554990 is 9945566.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7937 + ... + 14003.

It is an arithmetic number, because the mean of its divisors is an integer number (7495497).

Almost surely, 2^66554990 is an apocalyptic number.

66554990 is a deficient number, since it is larger than the sum of its proper divisors (53372962).

66554990 is a wasteful number, since it uses less digits than its factorization.

66554990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7171.

The product of its (nonzero) digits is 291600, while the sum is 44.

The square root of 66554990 is about 8158.1241716463. The cubic root of 66554990 is about 405.2535931467.

It can be divided in two parts, 665 and 54990, that added together give a palindrome (55655).

The spelling of 66554990 in words is "sixty-six million, five hundred fifty-four thousand, nine hundred ninety".