1421857 has 2 divisors, whose sum is σ = 1421858. Its totient is φ = 1421856.

The previous prime is 1421813. The next prime is 1421867. The reversal of 1421857 is 7581241.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 767376 + 654481 = 876^2 + 809^2 .

It is a cyclic number.

It is not a de Polignac number, because 1421857 - 2¹¹ = 1419809 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1421867) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 710928 + 710929.

It is an arithmetic number, because the mean of its divisors is an integer number (710929).

2^1421857 is an apocalyptic number.

It is an amenable number.

1421857 is a deficient number, since it is larger than the sum of its proper divisors (1).

1421857 is an equidigital number, since it uses as much as digits as its factorization.

1421857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2240, while the sum is 28.

The square root of 1421857 is about 1192.4164540965. The cubic root of 1421857 is about 112.4480616218.

It can be divided in two parts, 1421 and 857, that added together give a triangular number (2278 = T₆₇).

The spelling of 1421857 in words is "one million, four hundred twenty-one thousand, eight hundred fifty-seven".