2155020105500 has 96 divisors (see below), whose sum is σ = 4791091032000. Its totient is φ = 846555936000.

The previous prime is 2155020105473. The next prime is 2155020105583. The reversal of 2155020105500 is 55010205512.

It is a super-2 number, since 2×2155020105500² (a number of 25 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 2155020105500.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 30083726 + ... + 30155274.

It is an arithmetic number, because the mean of its divisors is an integer number (49907198250).

Almost surely, 2^{2155020105500} is an apocalyptic number.

2155020105500 is a gapful number since it is divisible by the number (20) 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 2155020105500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2395545516000).

2155020105500 is an abundant number, since it is smaller than the sum of its proper divisors (2636070926500).

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

2155020105500 is a wasteful number, since it uses less digits than its factorization.

2155020105500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72648 (or 72636 counting only the distinct ones).

The product of its (nonzero) digits is 2500, while the sum is 26.

The spelling of 2155020105500 in words is "two trillion, one hundred fifty-five billion, twenty million, one hundred five thousand, five hundred".