1028831291591 has 4 divisors (see below), whose sum is σ = 1028957583192. Its totient is φ = 1028704999992.

The previous prime is 1028831291569. The next prime is 1028831291659. The reversal of 1028831291591 is 1951921388201.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1028831291591 - 2³⁸ = 753953384647 is a prime.

It is a super-2 number, since 2×1028831291591² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1028831299591) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 63133580 + ... + 63149873.

It is an arithmetic number, because the mean of its divisors is an integer number (257239395798).

Almost surely, 2^{1028831291591} is an apocalyptic number.

1028831291591 is a deficient number, since it is larger than the sum of its proper divisors (126291601).

1028831291591 is an equidigital number, since it uses as much as digits as its factorization.

1028831291591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126291600.

The product of its (nonzero) digits is 311040, while the sum is 50.

The spelling of 1028831291591 in words is "one trillion, twenty-eight billion, eight hundred thirty-one million, two hundred ninety-one thousand, five hundred ninety-one".