9991149542 has 16 divisors (see below), whose sum is σ = 16912918800. Its totient is φ = 4384830240.

The previous prime is 9991149541. The next prime is 9991149551. The reversal of 9991149542 is 2459411999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9991149541) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7829417 + ... + 7830692.

It is an arithmetic number, because the mean of its divisors is an integer number (1057057425).

Almost surely, 2^9991149542 is an apocalyptic number.

9991149542 is a deficient number, since it is larger than the sum of its proper divisors (6921769258).

9991149542 is a wasteful number, since it uses less digits than its factorization.

9991149542 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15660151.

The product of its digits is 1049760, while the sum is 53.

The square root of 9991149542 is about 99955.7379143389. The cubic root of 9991149542 is about 2153.7989113060.

The spelling of 9991149542 in words is "nine billion, nine hundred ninety-one million, one hundred forty-nine thousand, five hundred forty-two".