21148427563 has 4 divisors (see below), whose sum is σ = 21150126448. Its totient is φ = 21146728680.

The previous prime is 21148427557. The next prime is 21148427569. The reversal of 21148427563 is 36572484112.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (21148427557) and next prime (21148427569).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21148427563 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21148427569) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 830631 + ... + 855712.

It is an arithmetic number, because the mean of its divisors is an integer number (5287531612).

Almost surely, 2^21148427563 is an apocalyptic number.

21148427563 is a deficient number, since it is larger than the sum of its proper divisors (1698885).

21148427563 is a wasteful number, since it uses less digits than its factorization.

21148427563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1698884.

The product of its digits is 322560, while the sum is 43.

The spelling of 21148427563 in words is "twenty-one billion, one hundred forty-eight million, four hundred twenty-seven thousand, five hundred sixty-three".