2121255000 has 320 divisors, whose sum is σ = 7760016000. Its totient is φ = 535248000.

The previous prime is 2121254999. The next prime is 2121255043. The reversal of 2121255000 is 5521212.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 2564587 + ... + 2565413.

It is an arithmetic number, because the mean of its divisors is an integer number (24250050).

Almost surely, 2^2121255000 is an apocalyptic number.

2121255000 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 2121255000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3880008000).

2121255000 is an abundant number, since it is smaller than the sum of its proper divisors (5638761000).

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

2121255000 is a wasteful number, since it uses less digits than its factorization.

2121255000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 881 (or 856 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 18.

The square root of 2121255000 is about 46057.0841456556. The cubic root of 2121255000 is about 1284.8851002757.

Adding to 2121255000 its reverse (5521212), we get a palindrome (2126776212).

The spelling of 2121255000 in words is "two billion, one hundred twenty-one million, two hundred fifty-five thousand".