66240520 has 16 divisors (see below), whose sum is σ = 149041260. Its totient is φ = 26496192.

The previous prime is 66240509. The next prime is 66240527. The reversal of 66240520 is 2504266.

It can be written as a sum of positive squares in 2 ways, for example, as 60000516 + 6240004 = 7746^2 + 2498^2 .

It is not an unprimeable number, because it can be changed into a prime (66240527) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 827967 + ... + 828046.

Almost surely, 2^66240520 is an apocalyptic number.

It is an amenable number.

66240520 is an abundant number, since it is smaller than the sum of its proper divisors (82800740).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66240520 is a wasteful number, since it uses less digits than its factorization.

66240520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1656024 (or 1656020 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 25.

The square root of 66240520 is about 8138.8279254448. The cubic root of 66240520 is about 404.6143155476.

Adding to 66240520 its reverse (2504266), we get a palindrome (68744786).

The spelling of 66240520 in words is "sixty-six million, two hundred forty thousand, five hundred twenty".