21152122563 has 16 divisors (see below), whose sum is σ = 33133395456. Its totient is φ = 11833355040.

The previous prime is 21152122559. The next prime is 21152122577. The reversal of 21152122563 is 36522125112.

It is not a de Polignac number, because 21152122563 - 2² = 21152122559 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21152122563.

It is not an unprimeable number, because it can be changed into a prime (21152122513) 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, 24652395 + ... + 24653252.

It is an arithmetic number, because the mean of its divisors is an integer number (2070837216).

Almost surely, 2^21152122563 is an apocalyptic number.

21152122563 is a deficient number, since it is larger than the sum of its proper divisors (11981272893).

21152122563 is a wasteful number, since it uses less digits than its factorization.

21152122563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49305674.

The product of its digits is 7200, while the sum is 30.

Adding to 21152122563 its reverse (36522125112), we get a palindrome (57674247675).

The spelling of 21152122563 in words is "twenty-one billion, one hundred fifty-two million, one hundred twenty-two thousand, five hundred sixty-three".