21224513021465 has 32 divisors (see below), whose sum is σ = 27772218714240. Its totient is φ = 15477312761856.

The previous prime is 21224513021431. The next prime is 21224513021513. The reversal of 21224513021465 is 56412031542212.

It is a cyclic number.

It is not a de Polignac number, because 21224513021465 - 2²⁸ = 21224244586009 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10468706 + ... + 12330564.

It is an arithmetic number, because the mean of its divisors is an integer number (867881834820).

Almost surely, 2^{21224513021465} is an apocalyptic number.

It is an amenable number.

21224513021465 is a deficient number, since it is larger than the sum of its proper divisors (6547705692775).

21224513021465 is a wasteful number, since it uses less digits than its factorization.

21224513021465 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1864073.

The product of its (nonzero) digits is 115200, while the sum is 38.

Adding to 21224513021465 its reverse (56412031542212), we get a palindrome (77636544563677).

The spelling of 21224513021465 in words is "twenty-one trillion, two hundred twenty-four billion, five hundred thirteen million, twenty-one thousand, four hundred sixty-five".