2129782211550 has 672 divisors, whose sum is σ = 6905132043264. Its totient is φ = 478480608000.

The previous prime is 2129782211521. The next prime is 2129782211551. The reversal of 2129782211550 is 551122879212.

It is a happy number.

2129782211550 is a `hidden beast` number, since 2 + 1 + 2 + 9 + 7 + 82 + 2 + 11 + 550 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 2129782211496 and 2129782211505.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2129782211551) by changing a digit.

It is a polite number, since it can be written in 335 ways as a sum of consecutive naturals, for example, 4941489835 + ... + 4941490265.

It is an arithmetic number, because the mean of its divisors is an integer number (10275494112).

Almost surely, 2^{2129782211550} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2129782211550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3452566021632).

2129782211550 is an abundant number, since it is smaller than the sum of its proper divisors (4775349831714).

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

2129782211550 is a wasteful number, since it uses less digits than its factorization.

2129782211550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 756 (or 736 counting only the distinct ones).

The product of its (nonzero) digits is 201600, while the sum is 45.

The spelling of 2129782211550 in words is "two trillion, one hundred twenty-nine billion, seven hundred eighty-two million, two hundred eleven thousand, five hundred fifty".