21978304570 has 8 divisors (see below), whose sum is σ = 39560948244. Its totient is φ = 8791321824.

The previous prime is 21978304553. The next prime is 21978304571. The reversal of 21978304570 is 7540387912.

It can be written as a sum of positive squares in 2 ways, for example, as 18344264481 + 3634040089 = 135441^2 + 60283^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21978304570.

It is not an unprimeable number, because it can be changed into a prime (21978304571) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1098915219 + ... + 1098915238.

Almost surely, 2^21978304570 is an apocalyptic number.

21978304570 is a deficient number, since it is larger than the sum of its proper divisors (17582643674).

21978304570 is a wasteful number, since it uses less digits than its factorization.

21978304570 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2197830464.

The product of its (nonzero) digits is 423360, while the sum is 46.

The spelling of 21978304570 in words is "twenty-one billion, nine hundred seventy-eight million, three hundred four thousand, five hundred seventy".