66889438 has 16 divisors (see below), whose sum is σ = 125092224. Its totient is φ = 26060760.

The previous prime is 66889429. The next prime is 66889439. The reversal of 66889438 is 83498866.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66889439) 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, 217020 + ... + 217327.

It is an arithmetic number, because the mean of its divisors is an integer number (7818264).

Almost surely, 2^66889438 is an apocalyptic number.

66889438 is a deficient number, since it is larger than the sum of its proper divisors (58202786).

66889438 is a wasteful number, since it uses less digits than its factorization.

66889438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 434367.

The product of its digits is 1990656, while the sum is 52.

The square root of 66889438 is about 8178.5963343351. The cubic root of 66889438 is about 405.9312776497.

The spelling of 66889438 in words is "sixty-six million, eight hundred eighty-nine thousand, four hundred thirty-eight".