1398521 has 2 divisors, whose sum is σ = 1398522. Its totient is φ = 1398520.

The previous prime is 1398517. The next prime is 1398541. The reversal of 1398521 is 1258931.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 929296 + 469225 = 964^2 + 685^2 .

It is an emirp because it is prime and its reverse (1258931) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1398521 - 2² = 1398517 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (1398541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 699260 + 699261.

It is an arithmetic number, because the mean of its divisors is an integer number (699261).

2^1398521 is an apocalyptic number.

It is an amenable number.

1398521 is a deficient number, since it is larger than the sum of its proper divisors (1).

1398521 is an equidigital number, since it uses as much as digits as its factorization.

1398521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2160, while the sum is 29.

The square root of 1398521 is about 1182.5907998966. The cubic root of 1398521 is about 111.8294864957.

The spelling of 1398521 in words is "one million, three hundred ninety-eight thousand, five hundred twenty-one".