766561333540 has 12 divisors (see below), whose sum is σ = 1609778800476. Its totient is φ = 306624533408.

The previous prime is 766561333507. The next prime is 766561333547. The reversal of 766561333540 is 45333165667.

766561333540 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 112119164964 + 654442168576 = 334842^2 + 808976^2 .

It is not an unprimeable number, because it can be changed into a prime (766561333547) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19164033319 + ... + 19164033358.

It is an arithmetic number, because the mean of its divisors is an integer number (134148233373).

Almost surely, 2^766561333540 is an apocalyptic number.

It is an amenable number.

766561333540 is an abundant number, since it is smaller than the sum of its proper divisors (843217466936).

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

766561333540 is a wasteful number, since it uses less digits than its factorization.

766561333540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38328066686 (or 38328066684 counting only the distinct ones).

The product of its (nonzero) digits is 4082400, while the sum is 49.

The spelling of 766561333540 in words is "seven hundred sixty-six billion, five hundred sixty-one million, three hundred thirty-three thousand, five hundred forty".