66438315 has 12 divisors (see below), whose sum is σ = 115159824. Its totient is φ = 35433744.

The previous prime is 66438313. The next prime is 66438331. The reversal of 66438315 is 51383466.

66438315 is a `hidden beast` number, since 6 + 643 + 8 + 3 + 1 + 5 = 666.

It is not a de Polignac number, because 66438315 - 2¹ = 66438313 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66438315.

It is not an unprimeable number, because it can be changed into a prime (66438313) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 738159 + ... + 738248.

It is an arithmetic number, because the mean of its divisors is an integer number (9596652).

Almost surely, 2^66438315 is an apocalyptic number.

66438315 is a deficient number, since it is larger than the sum of its proper divisors (48721509).

66438315 is a wasteful number, since it uses less digits than its factorization.

66438315 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1476418 (or 1476415 counting only the distinct ones).

The product of its digits is 51840, while the sum is 36.

The square root of 66438315 is about 8150.9701876525. The cubic root of 66438315 is about 405.0166431204.

The spelling of 66438315 in words is "sixty-six million, four hundred thirty-eight thousand, three hundred fifteen".