8191000400 has 60 divisors (see below), whose sum is σ = 21467878944. Its totient is φ = 2978544000.

The previous prime is 8191000399. The next prime is 8191000403. The reversal of 8191000400 is 40001918.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8191000403) 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 11 ways as a sum of consecutive naturals, for example, 926396 + ... + 935195.

Almost surely, 2^8191000400 is an apocalyptic number.

8191000400 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

8191000400 is an abundant number, since it is smaller than the sum of its proper divisors (13276878544).

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

8191000400 is a wasteful number, since it uses less digits than its factorization.

8191000400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1861620 (or 1861609 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 23.

The square root of 8191000400 is about 90504.1457613959. The cubic root of 8191000400 is about 2015.7916831970.

The spelling of 8191000400 in words is "eight billion, one hundred ninety-one million, four hundred", and thus it is an aban number.