1231291097784 has 80 divisors (see below), whose sum is σ = 3762278376120. Its totient is φ = 373118512320.

The previous prime is 1231291097767. The next prime is 1231291097821. The reversal of 1231291097784 is 4877901921321.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 1231291097784.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 86362899 + ... + 86377154.

Almost surely, 2^{1231291097784} is an apocalyptic number.

It is an amenable number.

1231291097784 is an abundant number, since it is smaller than the sum of its proper divisors (2530987278336).

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

1231291097784 is a wasteful number, since it uses less digits than its factorization.

1231291097784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 172740082 (or 172740069 counting only the distinct ones).

The product of its (nonzero) digits is 1524096, while the sum is 54.

The spelling of 1231291097784 in words is "one trillion, two hundred thirty-one billion, two hundred ninety-one million, ninety-seven thousand, seven hundred eighty-four".