66986243 has 4 divisors (see below), whose sum is σ = 68796720. Its totient is φ = 65175768.

The previous prime is 66986209. The next prime is 66986261. The reversal of 66986243 is 34268966.

66986243 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34268966 = 2 ⋅17134483.

It is a cyclic number.

It is not a de Polignac number, because 66986243 - 2²⁰ = 65937667 is a prime.

It is a super-3 number, since 3×66986243³ (a number of 24 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66986194 and 66986203.

It is not an unprimeable number, because it can be changed into a prime (66986263) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 905183 + ... + 905256.

It is an arithmetic number, because the mean of its divisors is an integer number (17199180).

Almost surely, 2^66986243 is an apocalyptic number.

66986243 is a deficient number, since it is larger than the sum of its proper divisors (1810477).

66986243 is a wasteful number, since it uses less digits than its factorization.

66986243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1810476.

The product of its digits is 373248, while the sum is 44.

The square root of 66986243 is about 8184.5123862085. The cubic root of 66986243 is about 406.1270097750.

The spelling of 66986243 in words is "sixty-six million, nine hundred eighty-six thousand, two hundred forty-three".