2185378947836 has 72 divisors (see below), whose sum is σ = 4481711410176. Its totient is φ = 929684874720.

The previous prime is 2185378947827. The next prime is 2185378947853. The reversal of 2185378947836 is 6387498735812.

It is a super-2 number, since 2×2185378947836² (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 2185378947836.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17420111 + ... + 17545113.

It is an arithmetic number, because the mean of its divisors is an integer number (62245991808).

Almost surely, 2^{2185378947836} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2185378947836, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2240855705088).

2185378947836 is an abundant number, since it is smaller than the sum of its proper divisors (2296332462340).

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

2185378947836 is a wasteful number, since it uses less digits than its factorization.

2185378947836 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 125679 (or 125670 counting only the distinct ones).

The product of its digits is 487710720, while the sum is 71.

The spelling of 2185378947836 in words is "two trillion, one hundred eighty-five billion, three hundred seventy-eight million, nine hundred forty-seven thousand, eight hundred thirty-six".