21920985448 has 8 divisors (see below), whose sum is σ = 41101847730. Its totient is φ = 10960492720.

The previous prime is 21920985433. The next prime is 21920985469. The reversal of 21920985448 is 84458902912.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 20534316804 + 1386668644 = 143298^2 + 37238^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×21920985448² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21920985395 and 21920985404.

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 as a sum of consecutive naturals, namely, 1370061583 + ... + 1370061598.

Almost surely, 2^21920985448 is an apocalyptic number.

It is an amenable number.

21920985448 is a deficient number, since it is larger than the sum of its proper divisors (19180862282).

21920985448 is a wasteful number, since it uses less digits than its factorization.

21920985448 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2740123187 (or 2740123183 counting only the distinct ones).

The product of its (nonzero) digits is 1658880, while the sum is 52.

The spelling of 21920985448 in words is "twenty-one billion, nine hundred twenty million, nine hundred eighty-five thousand, four hundred forty-eight".