21221523163424 has 24 divisors (see below), whose sum is σ = 41816172561408. Its totient is φ = 10601542830400.

The previous prime is 21221523163397. The next prime is 21221523163469. The reversal of 21221523163424 is 42436132512212.

It is a super-2 number, since 2×21221523163424² (a number of 27 digits) contains 22 as substring.

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 in 3 ways as a sum of consecutive naturals, for example, 288048572 + ... + 288122235.

It is an arithmetic number, because the mean of its divisors is an integer number (1742340523392).

Almost surely, 2^{21221523163424} is an apocalyptic number.

It is an amenable number.

21221523163424 is a deficient number, since it is larger than the sum of its proper divisors (20594649397984).

21221523163424 is a wasteful number, since it uses less digits than its factorization.

21221523163424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 576171968 (or 576171960 counting only the distinct ones).

The product of its digits is 138240, while the sum is 38.

Adding to 21221523163424 its reverse (42436132512212), we get a palindrome (63657655675636).

The spelling of 21221523163424 in words is "twenty-one trillion, two hundred twenty-one billion, five hundred twenty-three million, one hundred sixty-three thousand, four hundred twenty-four".