66415403 has 4 divisors (see below), whose sum is σ = 66549000. Its totient is φ = 66281808.

The previous prime is 66415373. The next prime is 66415463. The reversal of 66415403 is 30451466.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 66415403 - 2⁸ = 66415147 is a prime.

It is a super-2 number, since 2×66415403² = 8822011511304818, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66415463) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 66050 + ... + 67047.

It is an arithmetic number, because the mean of its divisors is an integer number (16637250).

Almost surely, 2^66415403 is an apocalyptic number.

66415403 is a deficient number, since it is larger than the sum of its proper divisors (133597).

66415403 is a wasteful number, since it uses less digits than its factorization.

66415403 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133596.

The product of its (nonzero) digits is 8640, while the sum is 29.

The square root of 66415403 is about 8149.5645895962. The cubic root of 66415403 is about 404.9700795861.

Adding to 66415403 its reverse (30451466), we get a palindrome (96866869).

The spelling of 66415403 in words is "sixty-six million, four hundred fifteen thousand, four hundred three".