66128499 has 12 divisors (see below), whose sum is σ = 95806776. Its totient is φ = 43952832.

The previous prime is 66128479. The next prime is 66128527. The reversal of 66128499 is 99482166.

It is a happy number.

It is not a de Polignac number, because 66128499 - 2⁹ = 66127987 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66128459) 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, 7869 + ... + 13934.

It is an arithmetic number, because the mean of its divisors is an integer number (7983898).

Almost surely, 2^66128499 is an apocalyptic number.

66128499 is a deficient number, since it is larger than the sum of its proper divisors (29678277).

66128499 is a wasteful number, since it uses less digits than its factorization.

66128499 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22146 (or 22143 counting only the distinct ones).

The product of its digits is 186624, while the sum is 45.

The square root of 66128499 is about 8131.9431257234. The cubic root of 66128499 is about 404.3861023908.

The spelling of 66128499 in words is "sixty-six million, one hundred twenty-eight thousand, four hundred ninety-nine".