66239545 has 8 divisors (see below), whose sum is σ = 79532424. Its totient is φ = 52961664.

The previous prime is 66239539. The next prime is 66239549. The reversal of 66239545 is 54593266.

It can be written as a sum of positive squares in 4 ways, for example, as 5071504 + 61168041 = 2252^2 + 7821^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66239545 - 2⁵ = 66239513 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66239498 and 66239507.

It is not an unprimeable number, because it can be changed into a prime (66239549) 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, 11967 + ... + 16603.

It is an arithmetic number, because the mean of its divisors is an integer number (9941553).

Almost surely, 2^66239545 is an apocalyptic number.

It is an amenable number.

66239545 is a deficient number, since it is larger than the sum of its proper divisors (13292879).

66239545 is a wasteful number, since it uses less digits than its factorization.

66239545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7499.

The product of its digits is 194400, while the sum is 40.

The square root of 66239545 is about 8138.7680271648. The cubic root of 66239545 is about 404.6123303534.

The spelling of 66239545 in words is "sixty-six million, two hundred thirty-nine thousand, five hundred forty-five".