1056721 has 2 divisors, whose sum is σ = 1056722. Its totient is φ = 1056720.

The previous prime is 1056719. The next prime is 1056739. The reversal of 1056721 is 1276501.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 876096 + 180625 = 936^2 + 425^2 .

It is an emirp because it is prime and its reverse (1276501) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1056721 - 2¹ = 1056719 is a prime.

It is a super-2 number, since 2×1056721² = 2233318543682, which contains 22 as substring.

Together with 1056719, it forms a pair of twin primes.

It is an alternating number because its digits alternate between odd and even.

It is a junction number, because it is equal to n+sod(n) for n = 1056692 and 1056701.

It is not a weakly prime, because it can be changed into another prime (1056521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 528360 + 528361.

It is an arithmetic number, because the mean of its divisors is an integer number (528361).

2^1056721 is an apocalyptic number.

It is an amenable number.

1056721 is a deficient number, since it is larger than the sum of its proper divisors (1).

1056721 is an equidigital number, since it uses as much as digits as its factorization.

1056721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 420, while the sum is 22.

The square root of 1056721 is about 1027.9693575200. The cubic root of 1056721 is about 101.8560380983.

The spelling of 1056721 in words is "one million, fifty-six thousand, seven hundred twenty-one".