55997811000 has 640 divisors, whose sum is σ = 209297088000. Its totient is φ = 13934592000.

The previous prime is 55997810983. The next prime is 55997811017. The reversal of 55997811000 is 11879955.

55997811000 is a `hidden beast` number, since 559 + 9 + 7 + 81 + 10 + 0 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (55997810983) and next prime (55997811017).

It is a Harshad number since it is a multiple of its sum of digits (45).

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 159 ways as a sum of consecutive naturals, for example, 72818616 + ... + 72819384.

It is an arithmetic number, because the mean of its divisors is an integer number (327026700).

Almost surely, 2^55997811000 is an apocalyptic number.

55997811000 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 55997811000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104648544000).

55997811000 is an abundant number, since it is smaller than the sum of its proper divisors (153299277000).

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

55997811000 is a wasteful number, since it uses less digits than its factorization.

55997811000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 862 (or 839 counting only the distinct ones).

The product of its (nonzero) digits is 113400, while the sum is 45.

The spelling of 55997811000 in words is "fifty-five billion, nine hundred ninety-seven million, eight hundred eleven thousand".