1370821 has 2 divisors, whose sum is σ = 1370822. Its totient is φ = 1370820.

The previous prime is 1370819. The next prime is 1370833. The reversal of 1370821 is 1280731.

1370821 is nontrivially palindromic in base 4.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1185921 + 184900 = 1089^2 + 430^2 .

It is a cyclic number.

It is not a de Polignac number, because 1370821 - 2¹ = 1370819 is a prime.

Together with 1370819, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 1370792 and 1370801.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1370861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 685410 + 685411.

It is an arithmetic number, because the mean of its divisors is an integer number (685411).

2^1370821 is an apocalyptic number.

It is an amenable number.

1370821 is a deficient number, since it is larger than the sum of its proper divisors (1).

1370821 is an equidigital number, since it uses as much as digits as its factorization.

1370821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 336, while the sum is 22.

The square root of 1370821 is about 1170.8206523631. The cubic root of 1370821 is about 111.0862355053.

The spelling of 1370821 in words is "one million, three hundred seventy thousand, eight hundred twenty-one".