21643287298040 has 32 divisors (see below), whose sum is σ = 48702124791360. Its totient is φ = 8656474320000.

The previous prime is 21643287298007. The next prime is 21643287298043. The reversal of 21643287298040 is 4089278234612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21643287298043) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25851536 + ... + 26675615.

It is an arithmetic number, because the mean of its divisors is an integer number (1521941399730).

Almost surely, 2^{21643287298040} is an apocalyptic number.

21643287298040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21643287298040 is an abundant number, since it is smaller than the sum of its proper divisors (27058837493320).

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

21643287298040 is a wasteful number, since it uses less digits than its factorization.

21643287298040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52537463 (or 52537459 counting only the distinct ones).

The product of its (nonzero) digits is 9289728, while the sum is 56.

The spelling of 21643287298040 in words is "twenty-one trillion, six hundred forty-three billion, two hundred eighty-seven million, two hundred ninety-eight thousand, forty".