66390415 has 32 divisors (see below), whose sum is σ = 99348480. Its totient is φ = 41468544.

The previous prime is 66390413. The next prime is 66390419. The reversal of 66390415 is 51409366.

It is not a de Polignac number, because 66390415 - 2¹ = 66390413 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66390413) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 35022 + ... + 36868.

It is an arithmetic number, because the mean of its divisors is an integer number (3104640).

Almost surely, 2^66390415 is an apocalyptic number.

66390415 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

66390415 is a deficient number, since it is larger than the sum of its proper divisors (32958065).

66390415 is a wasteful number, since it uses less digits than its factorization.

66390415 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1951.

The product of its (nonzero) digits is 19440, while the sum is 34.

The square root of 66390415 is about 8148.0313573280. The cubic root of 66390415 is about 404.9192848344.

The spelling of 66390415 in words is "sixty-six million, three hundred ninety thousand, four hundred fifteen".