1643461 has 2 divisors, whose sum is σ = 1643462. Its totient is φ = 1643460.

The previous prime is 1643431. The next prime is 1643491.

1643461 is nontrivially palindromic in base 10.

It is a balanced prime because it is at equal distance from previous prime (1643431) and next prime (1643491).

It can be written as a sum of positive squares in only one way, i.e., 1640961 + 2500 = 1281^2 + 50^2 .

It is a palprime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1643461 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1643431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 821730 + 821731.

It is an arithmetic number, because the mean of its divisors is an integer number (821731).

2^1643461 is an apocalyptic number.

It is an amenable number.

1643461 is a deficient number, since it is larger than the sum of its proper divisors (1).

1643461 is an equidigital number, since it uses as much as digits as its factorization.

1643461 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1728, while the sum is 25.

The square root of 1643461 is about 1281.9754287817. The cubic root of 1643461 is about 118.0102691436.

The spelling of 1643461 in words is "one million, six hundred forty-three thousand, four hundred sixty-one".