66403738 has 4 divisors (see below), whose sum is σ = 99605610. Its totient is φ = 33201868.

The previous prime is 66403721. The next prime is 66403747. The reversal of 66403738 is 83730466.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 33605209 + 32798529 = 5797^2 + 5727^2 .

It is a junction number, because it is equal to n+sod(n) for n = 66403697 and 66403706.

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 as a sum of consecutive naturals, namely, 16600933 + ... + 16600936.

Almost surely, 2^66403738 is an apocalyptic number.

66403738 is a deficient number, since it is larger than the sum of its proper divisors (33201872).

66403738 is a wasteful number, since it uses less digits than its factorization.

66403738 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33201871.

The product of its (nonzero) digits is 72576, while the sum is 37.

The square root of 66403738 is about 8148.8488757615. The cubic root of 66403738 is about 404.9463689589.

The spelling of 66403738 in words is "sixty-six million, four hundred three thousand, seven hundred thirty-eight".