9781663542 has 16 divisors (see below), whose sum is σ = 22358088192. Its totient is φ = 2794761000.

The previous prime is 9781663511. The next prime is 9781663553. The reversal of 9781663542 is 2453661879.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 116448334 + ... + 116448417.

It is an arithmetic number, because the mean of its divisors is an integer number (1397380512).

Almost surely, 2^9781663542 is an apocalyptic number.

9781663542 is an abundant number, since it is smaller than the sum of its proper divisors (12576424650).

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

9781663542 is a wasteful number, since it uses less digits than its factorization.

9781663542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 232896763.

The product of its digits is 2177280, while the sum is 51.

The square root of 9781663542 is about 98902.2929056753. The cubic root of 9781663542 is about 2138.6394488937.

The spelling of 9781663542 in words is "nine billion, seven hundred eighty-one million, six hundred sixty-three thousand, five hundred forty-two".