919191001000 has 64 divisors (see below), whose sum is σ = 2172203289360. Its totient is φ = 364036000000.

The previous prime is 919191000989. The next prime is 919191001007. The reversal of 919191001000 is 100191919.

It can be written as a sum of positive squares in 8 ways, for example, as 410847668676 + 508343332324 = 640974^2 + 712982^2 .

It is not an unprimeable number, because it can be changed into a prime (919191001007) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4449451 + ... + 4651450.

Almost surely, 2^919191001000 is an apocalyptic number.

It is an amenable number.

919191001000 is an abundant number, since it is smaller than the sum of its proper divisors (1253012288360).

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

919191001000 is a wasteful number, since it uses less digits than its factorization.

919191001000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9101023 (or 9101009 counting only the distinct ones).

The product of its (nonzero) digits is 729, while the sum is 31.

Adding to 919191001000 its reverse (100191919), we get a palindrome (919291192919).

The spelling of 919191001000 in words is "nine hundred nineteen billion, one hundred ninety-one million, one thousand".