21778352046 has 96 divisors (see below), whose sum is σ = 51941466720. Its totient is φ = 6540134400.

The previous prime is 21778351967. The next prime is 21778352069. The reversal of 21778352046 is 64025387712.

21778352046 is a `hidden beast` number, since 2 + 1 + 7 + 7 + 83 + 520 + 46 = 666.

It is a super-2 number, since 2×21778352046² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21778351992 and 21778352010.

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 47 ways as a sum of consecutive naturals, for example, 10926426 + ... + 10928418.

It is an arithmetic number, because the mean of its divisors is an integer number (541056945).

Almost surely, 2^21778352046 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21778352046, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25970733360).

21778352046 is an abundant number, since it is smaller than the sum of its proper divisors (30163114674).

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

21778352046 is a wasteful number, since it uses less digits than its factorization.

21778352046 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2482 (or 2479 counting only the distinct ones).

The product of its (nonzero) digits is 564480, while the sum is 45.

The spelling of 21778352046 in words is "twenty-one billion, seven hundred seventy-eight million, three hundred fifty-two thousand, forty-six".