1591189640 has 16 divisors (see below), whose sum is σ = 3580176780. Its totient is φ = 636475840.

The previous prime is 1591189627. The next prime is 1591189693. The reversal of 1591189640 is 469811951.

It can be written as a sum of positive squares in 2 ways, for example, as 1561356196 + 29833444 = 39514^2 + 5462^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1591189591 and 1591189600.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19889831 + ... + 19889910.

Almost surely, 2^1591189640 is an apocalyptic number.

1591189640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1591189640 is an abundant number, since it is smaller than the sum of its proper divisors (1988987140).

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

1591189640 is a wasteful number, since it uses less digits than its factorization.

1591189640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39779752 (or 39779748 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 44.

The square root of 1591189640 is about 39889.7184748150. The cubic root of 1591189640 is about 1167.4563386686.

The spelling of 1591189640 in words is "one billion, five hundred ninety-one million, one hundred eighty-nine thousand, six hundred forty".