21267520544 has 24 divisors (see below), whose sum is σ = 41904577260. Its totient is φ = 10625088256.

The previous prime is 21267520537. The next prime is 21267520567. The reversal of 21267520544 is 44502576212.

It can be written as a sum of positive squares in 2 ways, for example, as 21263472400 + 4048144 = 145820^2 + 2012^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21267520498 and 21267520507.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 231059 + ... + 309714.

Almost surely, 2^21267520544 is an apocalyptic number.

It is an amenable number.

21267520544 is a deficient number, since it is larger than the sum of its proper divisors (20637056716).

21267520544 is a wasteful number, since it uses less digits than its factorization.

21267520544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 542012 (or 542004 counting only the distinct ones).

The product of its (nonzero) digits is 134400, while the sum is 38.

The spelling of 21267520544 in words is "twenty-one billion, two hundred sixty-seven million, five hundred twenty thousand, five hundred forty-four".