21944161627864 has 256 divisors, whose sum is σ = 50610438144000. Its totient is φ = 8722877990400.

The previous prime is 21944161627841. The next prime is 21944161627891. The reversal of 21944161627864 is 46872616144912.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 863149057 + ... + 863174479.

It is an arithmetic number, because the mean of its divisors is an integer number (197697024000).

Almost surely, 2^{21944161627864} 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 21944161627864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25305219072000).

21944161627864 is an abundant number, since it is smaller than the sum of its proper divisors (28666276516136).

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

21944161627864 is a wasteful number, since it uses less digits than its factorization.

21944161627864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25734 (or 25730 counting only the distinct ones).

The product of its digits is 27869184, while the sum is 61.

The spelling of 21944161627864 in words is "twenty-one trillion, nine hundred forty-four billion, one hundred sixty-one million, six hundred twenty-seven thousand, eight hundred sixty-four".