66415 has 8 divisors (see below), whose sum is σ = 82080. Its totient is φ = 51552.

The previous prime is 66413. The next prime is 66431. The reversal of 66415 is 51466.

66415 = 23² + 24² + ... + 59².

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66415 - 2¹ = 66413 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66413) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6 + ... + 364.

It is an arithmetic number, because the mean of its divisors is an integer number (10260).

2⁶⁶⁴¹⁵ is an apocalyptic number.

66415 is a deficient number, since it is larger than the sum of its proper divisors (15665).

66415 is a wasteful number, since it uses less digits than its factorization.

66415 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 401.

The product of its digits is 720, while the sum is 22.

The square root of 66415 is about 257.7110785356. The cubic root of 66415 is about 40.4969260483.

The spelling of 66415 in words is "sixty-six thousand, four hundred fifteen".