66408615 has 48 divisors (see below), whose sum is σ = 141680448. Its totient is φ = 28021248.

The previous prime is 66408607. The next prime is 66408619. The reversal of 66408615 is 51680466.

66408615 is a `hidden beast` number, since 6 + 640 + 8 + 6 + 1 + 5 = 666.

It is not a de Polignac number, because 66408615 - 2³ = 66408607 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 66408615.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66408619) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4014 + ... + 12203.

It is an arithmetic number, because the mean of its divisors is an integer number (2951676).

Almost surely, 2^66408615 is an apocalyptic number.

66408615 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

66408615 is an abundant number, since it is smaller than the sum of its proper divisors (75271833).

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

66408615 is a wasteful number, since it uses less digits than its factorization.

66408615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16248 (or 16245 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 66408615 is about 8149.1481149872. The cubic root of 66408615 is about 404.9562824324.

The spelling of 66408615 in words is "sixty-six million, four hundred eight thousand, six hundred fifteen".