1991291410 has 16 divisors (see below), whose sum is σ = 3604130712. Its totient is φ = 792115200.

The previous prime is 1991291399. The next prime is 1991291513. The reversal of 1991291410 is 141921991.

It can be written as a sum of positive squares in 4 ways, for example, as 463497841 + 1527793569 = 21529^2 + 39087^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1991291410.

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, 548271 + ... + 551890.

Almost surely, 2^1991291410 is an apocalyptic number.

1991291410 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1991291410 is a deficient number, since it is larger than the sum of its proper divisors (1612839302).

1991291410 is a wasteful number, since it uses less digits than its factorization.

1991291410 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1100349.

The product of its (nonzero) digits is 5832, while the sum is 37.

The square root of 1991291410 is about 44623.8883334924. Note that the first 3 decimals coincide. The cubic root of 1991291410 is about 1258.0896999286.

The spelling of 1991291410 in words is "one billion, nine hundred ninety-one million, two hundred ninety-one thousand, four hundred ten".