66289405 has 36 divisors (see below), whose sum is σ = 100262772. Its totient is φ = 41932800.

The previous prime is 66289393. The next prime is 66289417. The reversal of 66289405 is 50498266.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (66289393) and next prime (66289417).

It can be written as a sum of positive squares in 6 ways, for example, as 582169 + 65707236 = 763^2 + 8106^2 .

It is not a de Polignac number, because 66289405 - 2⁷ = 66289277 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 40605 + ... + 42205.

It is an arithmetic number, because the mean of its divisors is an integer number (2785077).

Almost surely, 2^66289405 is an apocalyptic number.

66289405 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

66289405 is a deficient number, since it is larger than the sum of its proper divisors (33973367).

66289405 is a wasteful number, since it uses less digits than its factorization.

66289405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1646 (or 1626 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 40.

The square root of 66289405 is about 8141.8305681216. The cubic root of 66289405 is about 404.7138251684.

The spelling of 66289405 in words is "sixty-six million, two hundred eighty-nine thousand, four hundred five".