991235661142 has 16 divisors (see below), whose sum is σ = 1489504665600. Its totient is φ = 494734375080.

The previous prime is 991235661029. The next prime is 991235661161. The reversal of 991235661142 is 241166532199.

It is a super-3 number, since 3×991235661142³ (a number of 37 digits) contains 333 as substring.

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, 7699659 + ... + 7827337.

It is an arithmetic number, because the mean of its divisors is an integer number (93094041600).

Almost surely, 2^991235661142 is an apocalyptic number.

991235661142 is a deficient number, since it is larger than the sum of its proper divisors (498269004458).

991235661142 is a wasteful number, since it uses less digits than its factorization.

991235661142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134571.

The product of its digits is 699840, while the sum is 49.

The spelling of 991235661142 in words is "nine hundred ninety-one billion, two hundred thirty-five million, six hundred sixty-one thousand, one hundred forty-two".