698210021 has 2 divisors, whose sum is σ = 698210022. Its totient is φ = 698210020.

The previous prime is 698209933. The next prime is 698210047. The reversal of 698210021 is 120012896.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 425596900 + 272613121 = 20630^2 + 16511^2 .

It is a cyclic number.

It is not a de Polignac number, because 698210021 - 2¹⁰ = 698208997 is a prime.

It is a Chen prime.

It is equal to p_36165071 and since 698210021 and 36165071 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (698210321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 349105010 + 349105011.

It is an arithmetic number, because the mean of its divisors is an integer number (349105011).

Almost surely, 2^698210021 is an apocalyptic number.

It is an amenable number.

698210021 is a deficient number, since it is larger than the sum of its proper divisors (1).

698210021 is an equidigital number, since it uses as much as digits as its factorization.

698210021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728, while the sum is 29.

The square root of 698210021 is about 26423.6640343462. The cubic root of 698210021 is about 887.1465321506.

The spelling of 698210021 in words is "six hundred ninety-eight million, two hundred ten thousand, twenty-one".