543971921 has 2 divisors, whose sum is σ = 543971922. Its totient is φ = 543971920.

The previous prime is 543971839. The next prime is 543971927. The reversal of 543971921 is 129179345.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 539911696 + 4060225 = 23236^2 + 2015^2 .

It is a cyclic number.

It is not a de Polignac number, because 543971921 - 2¹⁰ = 543970897 is a prime.

It is a Chen prime.

It is equal to p_28545584 and since 543971921 and 28545584 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (543971927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 271985960 + 271985961.

It is an arithmetic number, because the mean of its divisors is an integer number (271985961).

Almost surely, 2^543971921 is an apocalyptic number.

It is an amenable number.

543971921 is a deficient number, since it is larger than the sum of its proper divisors (1).

543971921 is an equidigital number, since it uses as much as digits as its factorization.

543971921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 68040, while the sum is 41.

The square root of 543971921 is about 23323.2056330171. The cubic root of 543971921 is about 816.3169749465.

The spelling of 543971921 in words is "five hundred forty-three million, nine hundred seventy-one thousand, nine hundred twenty-one".