21428164543 has 2 divisors, whose sum is σ = 21428164544. Its totient is φ = 21428164542.

The previous prime is 21428164507. The next prime is 21428164547. The reversal of 21428164543 is 34546182412.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21428164543 - 2⁹ = 21428164031 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21428164496 and 21428164505.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21428164547) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10714082271 + 10714082272.

It is an arithmetic number, because the mean of its divisors is an integer number (10714082272).

Almost surely, 2^21428164543 is an apocalyptic number.

21428164543 is a deficient number, since it is larger than the sum of its proper divisors (1).

21428164543 is an equidigital number, since it uses as much as digits as its factorization.

21428164543 is an evil number, because the sum of its binary digits is even.

The product of its digits is 184320, while the sum is 40.

The spelling of 21428164543 in words is "twenty-one billion, four hundred twenty-eight million, one hundred sixty-four thousand, five hundred forty-three".