66418438 has 4 divisors (see below), whose sum is σ = 99627660. Its totient is φ = 33209218.

The previous prime is 66418427. The next prime is 66418489. The reversal of 66418438 is 83481466.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×66418438² = 8822817812719688, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 66418438.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16604608 + ... + 16604611.

It is an arithmetic number, because the mean of its divisors is an integer number (24906915).

Almost surely, 2^66418438 is an apocalyptic number.

66418438 is a deficient number, since it is larger than the sum of its proper divisors (33209222).

66418438 is a wasteful number, since it uses less digits than its factorization.

66418438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33209221.

The product of its digits is 110592, while the sum is 40.

The square root of 66418438 is about 8149.7507937360. The cubic root of 66418438 is about 404.9762481625.

The spelling of 66418438 in words is "sixty-six million, four hundred eighteen thousand, four hundred thirty-eight".