21531363848 has 8 divisors (see below), whose sum is σ = 40371307230. Its totient is φ = 10765681920.

The previous prime is 21531363839. The next prime is 21531363853. The reversal of 21531363848 is 84836313512.

It can be written as a sum of positive squares in only one way, i.e., 19466388484 + 2064975364 = 139522^2 + 45442^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×21531363848² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21531363799 and 21531363808.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1345710233 + ... + 1345710248.

Almost surely, 2^21531363848 is an apocalyptic number.

It is an amenable number.

21531363848 is a deficient number, since it is larger than the sum of its proper divisors (18839943382).

21531363848 is a wasteful number, since it uses less digits than its factorization.

21531363848 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2691420487 (or 2691420483 counting only the distinct ones).

The product of its digits is 414720, while the sum is 44.

The spelling of 21531363848 in words is "twenty-one billion, five hundred thirty-one million, three hundred sixty-three thousand, eight hundred forty-eight".