66538648 has 32 divisors (see below), whose sum is σ = 140497920. Its totient is φ = 29268000.

The previous prime is 66538643. The next prime is 66538649. The reversal of 66538648 is 84683566.

It is a junction number, because it is equal to n+sod(n) for n = 66538598 and 66538607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66538643) 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, 9468 + ... + 14923.

It is an arithmetic number, because the mean of its divisors is an integer number (4390560).

Almost surely, 2^66538648 is an apocalyptic number.

It is an amenable number.

66538648 is an abundant number, since it is smaller than the sum of its proper divisors (73959272).

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

66538648 is a wasteful number, since it uses less digits than its factorization.

66538648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24439 (or 24435 counting only the distinct ones).

The product of its digits is 829440, while the sum is 46.

The square root of 66538648 is about 8157.1225318736. The cubic root of 66538648 is about 405.2204215977.

The spelling of 66538648 in words is "sixty-six million, five hundred thirty-eight thousand, six hundred forty-eight".