65531618 has 4 divisors (see below), whose sum is σ = 98297430. Its totient is φ = 32765808.

The previous prime is 65531581. The next prime is 65531633. The reversal of 65531618 is 81613556.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 65496649 + 34969 = 8093^2 + 187^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16382903 + ... + 16382906.

Almost surely, 2^65531618 is an apocalyptic number.

65531618 is a deficient number, since it is larger than the sum of its proper divisors (32765812).

65531618 is a wasteful number, since it uses less digits than its factorization.

65531618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32765811.

The product of its digits is 21600, while the sum is 35.

The square root of 65531618 is about 8095.1601590086. The cubic root of 65531618 is about 403.1657498057.

The spelling of 65531618 in words is "sixty-five million, five hundred thirty-one thousand, six hundred eighteen".