6645242564 has 6 divisors (see below), whose sum is σ = 11629174494. Its totient is φ = 3322621280.

The previous prime is 6645242561. The next prime is 6645242603. The reversal of 6645242564 is 4652425466.

It can be written as a sum of positive squares in only one way, i.e., 5505640000 + 1139602564 = 74200^2 + 33758^2 .

It is not an unprimeable number, because it can be changed into a prime (6645242561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 830655317 + ... + 830655324.

It is an arithmetic number, because the mean of its divisors is an integer number (1938195749).

Almost surely, 2^6645242564 is an apocalyptic number.

It is an amenable number.

6645242564 is a deficient number, since it is larger than the sum of its proper divisors (4983931930).

6645242564 is a wasteful number, since it uses less digits than its factorization.

6645242564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1661310645 (or 1661310643 counting only the distinct ones).

The product of its digits is 1382400, while the sum is 44.

The square root of 6645242564 is about 81518.3572209352. The cubic root of 6645242564 is about 1880.0538090076.

The spelling of 6645242564 in words is "six billion, six hundred forty-five million, two hundred forty-two thousand, five hundred sixty-four".