66518433 has 12 divisors (see below), whose sum is σ = 101734308. Its totient is φ = 41736960.

The previous prime is 66518423. The next prime is 66518443. The reversal of 66518433 is 33481566.

It is an interprime number because it is at equal distance from previous prime (66518423) and next prime (66518443).

It can be written as a sum of positive squares in 2 ways, for example, as 31270464 + 35247969 = 5592^2 + 5937^2 .

It is not a de Polignac number, because 66518433 - 2⁵ = 66518401 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (66518423) 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, 217228 + ... + 217533.

It is an arithmetic number, because the mean of its divisors is an integer number (8477859).

Almost surely, 2^66518433 is an apocalyptic number.

It is an amenable number.

66518433 is a deficient number, since it is larger than the sum of its proper divisors (35215875).

66518433 is a wasteful number, since it uses less digits than its factorization.

66518433 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 434784 (or 434781 counting only the distinct ones).

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

The square root of 66518433 is about 8155.8833365859. The cubic root of 66518433 is about 405.1793809857.

Adding to 66518433 its reverse (33481566), we get a palindrome (99999999).

The spelling of 66518433 in words is "sixty-six million, five hundred eighteen thousand, four hundred thirty-three".