64518644 has 6 divisors (see below), whose sum is σ = 112907634. Its totient is φ = 32259320.

The previous prime is 64518617. The next prime is 64518647. The reversal of 64518644 is 44681546.

It can be written as a sum of positive squares in only one way, i.e., 33292900 + 31225744 = 5770^2 + 5588^2 .

It is a junction number, because it is equal to n+sod(n) for n = 64518598 and 64518607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64518647) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8064827 + ... + 8064834.

It is an arithmetic number, because the mean of its divisors is an integer number (18817939).

Almost surely, 2^64518644 is an apocalyptic number.

It is an amenable number.

64518644 is a deficient number, since it is larger than the sum of its proper divisors (48388990).

64518644 is a wasteful number, since it uses less digits than its factorization.

64518644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16129665 (or 16129663 counting only the distinct ones).

The product of its digits is 92160, while the sum is 38.

The square root of 64518644 is about 8032.3498429787. The cubic root of 64518644 is about 401.0776026577.

The spelling of 64518644 in words is "sixty-four million, five hundred eighteen thousand, six hundred forty-four".