21248843904 has 48 divisors (see below), whose sum is σ = 61145765070. Its totient is φ = 7082947584.

The previous prime is 21248843897. The next prime is 21248843911. The reversal of 21248843904 is 40934884212.

21248843904 is a `hidden beast` number, since 212 + 48 + 8 + 4 + 390 + 4 = 666.

It is an interprime number because it is at equal distance from previous prime (21248843897) and next prime (21248843911).

It can be written as a sum of positive squares in only one way, i.e., 21243645504 + 5198400 = 145752^2 + 2280^2 .

It is a tau number, because it is divible by the number of its divisors (48).

It is a super-2 number, since 2×21248843904² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21248843904.

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 in 5 ways as a sum of consecutive naturals, for example, 9221437 + ... + 9223740.

Almost surely, 2^21248843904 is an apocalyptic number.

21248843904 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21248843904 is an abundant number, since it is smaller than the sum of its proper divisors (39896921166).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21248843904 is a wasteful number, since it uses less digits than its factorization.

21248843904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18445197 (or 18445182 counting only the distinct ones).

The product of its (nonzero) digits is 442368, while the sum is 45.

The spelling of 21248843904 in words is "twenty-one billion, two hundred forty-eight million, eight hundred forty-three thousand, nine hundred four".