21576285120784 has 45 divisors (see below), whose sum is σ = 42502832028111. Its totient is φ = 10610730360960.

The previous prime is 21576285120781. The next prime is 21576285120809. The reversal of 21576285120784 is 48702158267512.

The square root of 21576285120784 is 4645028.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 20223548643600 + 1352736477184 = 4497060^2 + 1163072^2 .

It is a super-2 number, since 2×21576285120784² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21576285120781) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1133377314 + ... + 1133396350.

Almost surely, 2^{21576285120784} is an apocalyptic number.

21576285120784 is the 4645028-th square number.

It is an amenable number.

21576285120784 is a deficient number, since it is larger than the sum of its proper divisors (20926546907327).

21576285120784 is an frugal number, since it uses more digits than its factorization.

21576285120784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38204 (or 19100 counting only the distinct ones).

The product of its (nonzero) digits is 15052800, while the sum is 58.

The spelling of 21576285120784 in words is "twenty-one trillion, five hundred seventy-six billion, two hundred eighty-five million, one hundred twenty thousand, seven hundred eighty-four".