1556491 has 2 divisors, whose sum is σ = 1556492. Its totient is φ = 1556490.

The previous prime is 1556473. The next prime is 1556501. The reversal of 1556491 is 1946551.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1556491 - 2⁷ = 1556363 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1556431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 778245 + 778246.

It is an arithmetic number, because the mean of its divisors is an integer number (778246).

2^1556491 is an apocalyptic number.

1556491 is a deficient number, since it is larger than the sum of its proper divisors (1).

1556491 is an equidigital number, since it uses as much as digits as its factorization.

1556491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5400, while the sum is 31.

The square root of 1556491 is about 1247.5940846285. The cubic root of 1556491 is about 115.8907761027.

The spelling of 1556491 in words is "one million, five hundred fifty-six thousand, four hundred ninety-one".