75781669648 has 20 divisors (see below), whose sum is σ = 146950095708. Its totient is φ = 37859064320.

The previous prime is 75781669643. The next prime is 75781669679. The reversal of 75781669648 is 84696618757.

It can be written as a sum of positive squares in 2 ways, for example, as 36400060944 + 39381608704 = 190788^2 + 198448^2 .

It is a super-2 number, since 2×75781669648² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (75781669643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1965973 + ... + 2004148.

Almost surely, 2^75781669648 is an apocalyptic number.

It is an amenable number.

75781669648 is a deficient number, since it is larger than the sum of its proper divisors (71168426060).

75781669648 is a wasteful number, since it uses less digits than its factorization.

75781669648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3971322 (or 3971316 counting only the distinct ones).

The product of its digits is 121927680, while the sum is 67.

The spelling of 75781669648 in words is "seventy-five billion, seven hundred eighty-one million, six hundred sixty-nine thousand, six hundred forty-eight".