84057428921 has 2 divisors, whose sum is σ = 84057428922. Its totient is φ = 84057428920.

The previous prime is 84057428909. The next prime is 84057428927. The reversal of 84057428921 is 12982475048.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 46856663296 + 37200765625 = 216464^2 + 192875^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-84057428921 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 84057428921.

It is not a weakly prime, because it can be changed into another prime (84057428927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42028714460 + 42028714461.

It is an arithmetic number, because the mean of its divisors is an integer number (42028714461).

Almost surely, 2^84057428921 is an apocalyptic number.

It is an amenable number.

84057428921 is a deficient number, since it is larger than the sum of its proper divisors (1).

84057428921 is an equidigital number, since it uses as much as digits as its factorization.

84057428921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1290240, while the sum is 50.

The spelling of 84057428921 in words is "eighty-four billion, fifty-seven million, four hundred twenty-eight thousand, nine hundred twenty-one".