21795646278 has 64 divisors (see below), whose sum is σ = 50878056960. Its totient is φ = 6096288000.

The previous prime is 21795646211. The next prime is 21795646307. The reversal of 21795646278 is 87264659712.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 348673 + ... + 406403.

It is an arithmetic number, because the mean of its divisors is an integer number (794969640).

Almost surely, 2^21795646278 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21795646278, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25439028480).

21795646278 is an abundant number, since it is smaller than the sum of its proper divisors (29082410682).

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

21795646278 is a wasteful number, since it uses less digits than its factorization.

21795646278 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57933.

The product of its digits is 10160640, while the sum is 57.

The spelling of 21795646278 in words is "twenty-one billion, seven hundred ninety-five million, six hundred forty-six thousand, two hundred seventy-eight".