21231456440440 has 32 divisors (see below), whose sum is σ = 47772206892000. Its totient is φ = 8492328371584.

The previous prime is 21231456440417. The next prime is 21231456440483. The reversal of 21231456440440 is 4404465413212.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 21231456440393 and 21231456440402.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6587995 + ... + 9266314.

It is an arithmetic number, because the mean of its divisors is an integer number (1492881465375).

Almost surely, 2^{21231456440440} is an apocalyptic number.

21231456440440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21231456440440 is an abundant number, since it is smaller than the sum of its proper divisors (26540750451560).

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

21231456440440 is a wasteful number, since it uses less digits than its factorization.

21231456440440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15887799 (or 15887795 counting only the distinct ones).

The product of its (nonzero) digits is 368640, while the sum is 40.

The spelling of 21231456440440 in words is "twenty-one trillion, two hundred thirty-one billion, four hundred fifty-six million, four hundred forty thousand, four hundred forty".