661232130642 has 24 divisors (see below), whose sum is σ = 1471390418316. Its totient is φ = 214453663776.

The previous prime is 661232130619. The next prime is 661232130697. The reversal of 661232130642 is 246031232166.

661232130642 is a `hidden beast` number, since 6 + 6 + 1 + 2 + 3 + 2 + 1 + 3 + 0 + 642 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 637057789281 + 24174341361 = 798159^2 + 155481^2 .

It is a junction number, because it is equal to n+sod(n) for n = 661232130597 and 661232130606.

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, 496419853 + ... + 496421184.

Almost surely, 2^661232130642 is an apocalyptic number.

661232130642 is an abundant number, since it is smaller than the sum of its proper divisors (810158287674).

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

661232130642 is a wasteful number, since it uses less digits than its factorization.

661232130642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 992841082 (or 992841079 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 36.

The spelling of 661232130642 in words is "six hundred sixty-one billion, two hundred thirty-two million, one hundred thirty thousand, six hundred forty-two".