21201555432443 has 2 divisors, whose sum is σ = 21201555432444. Its totient is φ = 21201555432442.

The previous prime is 21201555432389. The next prime is 21201555432467. The reversal of 21201555432443 is 34423455510212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21201555432443 - 2³⁸ = 20926677525499 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21201555432443.

It is not a weakly prime, because it can be changed into another prime (21201555437443) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10600777716221 + 10600777716222.

It is an arithmetic number, because the mean of its divisors is an integer number (10600777716222).

Almost surely, 2^{21201555432443} is an apocalyptic number.

21201555432443 is a deficient number, since it is larger than the sum of its proper divisors (1).

21201555432443 is an equidigital number, since it uses as much as digits as its factorization.

21201555432443 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 576000, while the sum is 41.

The spelling of 21201555432443 in words is "twenty-one trillion, two hundred one billion, five hundred fifty-five million, four hundred thirty-two thousand, four hundred forty-three".