811899998550 has 72 divisors (see below), whose sum is σ = 2190666768264. Its totient is φ = 215577425280.

The previous prime is 811899998521. The next prime is 811899998593. The reversal of 811899998550 is 55899998118.

It is a congruent number.

It is an unprimeable number.

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 35 ways as a sum of consecutive naturals, for example, 3766872 + ... + 3976571.

It is an arithmetic number, because the mean of its divisors is an integer number (30425927337).

Almost surely, 2^811899998550 is an apocalyptic number.

811899998550 is an abundant number, since it is smaller than the sum of its proper divisors (1378766769714).

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

811899998550 is a wasteful number, since it uses less digits than its factorization.

811899998550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7743694 (or 7743686 counting only the distinct ones).

The product of its (nonzero) digits is 83980800, while the sum is 72.

The spelling of 811899998550 in words is "eight hundred eleven billion, eight hundred ninety-nine million, nine hundred ninety-eight thousand, five hundred fifty".