21256043540323 has 12 divisors (see below), whose sum is σ = 22737154436920. Its totient is φ = 19859033579616.

The previous prime is 21256043540321. The next prime is 21256043540359. The reversal of 21256043540323 is 32304534065212.

It is not a de Polignac number, because 21256043540323 - 2¹ = 21256043540321 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21256043540321) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 467204658 + ... + 467250151.

Almost surely, 2^{21256043540323} is an apocalyptic number.

21256043540323 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

21256043540323 is a deficient number, since it is larger than the sum of its proper divisors (1481110896597).

21256043540323 is an equidigital number, since it uses as much as digits as its factorization.

21256043540323 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 934454898 (or 934454875 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 40.

The spelling of 21256043540323 in words is "twenty-one trillion, two hundred fifty-six billion, forty-three million, five hundred forty thousand, three hundred twenty-three".