521761607642 has 24 divisors (see below), whose sum is σ = 860304078228. Its totient is φ = 237152171520.

The previous prime is 521761607599. The next prime is 521761607657. The reversal of 521761607642 is 246706167125.

It can be written as a sum of positive squares in 2 ways, for example, as 512153491201 + 9608116441 = 715649^2 + 98021^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6044168 + ... + 6129884.

Almost surely, 2^521761607642 is an apocalyptic number.

521761607642 is a deficient number, since it is larger than the sum of its proper divisors (338542470586).

521761607642 is a wasteful number, since it uses less digits than its factorization.

521761607642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110894 (or 110883 counting only the distinct ones).

The product of its (nonzero) digits is 846720, while the sum is 47.

The spelling of 521761607642 in words is "five hundred twenty-one billion, seven hundred sixty-one million, six hundred seven thousand, six hundred forty-two".