21320241563 has 16 divisors (see below), whose sum is σ = 22570686720. Its totient is φ = 20082869856.

The previous prime is 21320241559. The next prime is 21320241571. The reversal of 21320241563 is 36514202312.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21320241563 - 2² = 21320241559 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21320241763) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3822845 + ... + 3828417.

It is an arithmetic number, because the mean of its divisors is an integer number (1410667920).

Almost surely, 2^21320241563 is an apocalyptic number.

21320241563 is a deficient number, since it is larger than the sum of its proper divisors (1250445157).

21320241563 is a wasteful number, since it uses less digits than its factorization.

21320241563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6706.

The product of its (nonzero) digits is 8640, while the sum is 29.

Adding to 21320241563 its reverse (36514202312), we get a palindrome (57834443875).

The spelling of 21320241563 in words is "twenty-one billion, three hundred twenty million, two hundred forty-one thousand, five hundred sixty-three".