21163004440 has 32 divisors (see below), whose sum is σ = 48778148160. Its totient is φ = 8258732800.

The previous prime is 21163004437. The next prime is 21163004449. The reversal of 21163004440 is 4440036112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21163004449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6450496 + ... + 6453775.

It is an arithmetic number, because the mean of its divisors is an integer number (1524317130).

Almost surely, 2^21163004440 is an apocalyptic number.

21163004440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21163004440 is an abundant number, since it is smaller than the sum of its proper divisors (27615143720).

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

21163004440 is a wasteful number, since it uses less digits than its factorization.

21163004440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12904323 (or 12904319 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 25.

The spelling of 21163004440 in words is "twenty-one billion, one hundred sixty-three million, four thousand, four hundred forty".