2185441661621 has 16 divisors (see below), whose sum is σ = 2228399581440. Its totient is φ = 2142800732160.

The previous prime is 2185441661597. The next prime is 2185441661633. The reversal of 2185441661621 is 1261661445812.

It is a de Polignac number, because none of the positive numbers 2^k-2185441661621 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2185441661521) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22698260 + ... + 22794338.

It is an arithmetic number, because the mean of its divisors is an integer number (139274973840).

Almost surely, 2^{2185441661621} is an apocalyptic number.

It is an amenable number.

2185441661621 is a deficient number, since it is larger than the sum of its proper divisors (42957919819).

2185441661621 is a wasteful number, since it uses less digits than its factorization.

2185441661621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97724.

The product of its digits is 552960, while the sum is 47.

The spelling of 2185441661621 in words is "two trillion, one hundred eighty-five billion, four hundred forty-one million, six hundred sixty-one thousand, six hundred twenty-one".