21655416043423 has 2 divisors, whose sum is σ = 21655416043424. Its totient is φ = 21655416043422.

The previous prime is 21655416043321. The next prime is 21655416043439. The reversal of 21655416043423 is 32434061455612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21655416043423 - 2²⁵ = 21655382488991 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21655416043483) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10827708021711 + 10827708021712.

It is an arithmetic number, because the mean of its divisors is an integer number (10827708021712).

Almost surely, 2^{21655416043423} is an apocalyptic number.

21655416043423 is a deficient number, since it is larger than the sum of its proper divisors (1).

21655416043423 is an equidigital number, since it uses as much as digits as its factorization.

21655416043423 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2073600, while the sum is 46.

The spelling of 21655416043423 in words is "twenty-one trillion, six hundred fifty-five billion, four hundred sixteen million, forty-three thousand, four hundred twenty-three".