1871491 has 2 divisors, whose sum is σ = 1871492. Its totient is φ = 1871490.

The previous prime is 1871477. The next prime is 1871503. The reversal of 1871491 is 1941781.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1871491 - 2⁵ = 1871459 is a prime.

It is not a weakly prime, because it can be changed into another prime (1871461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 935745 + 935746.

It is an arithmetic number, because the mean of its divisors is an integer number (935746).

2^1871491 is an apocalyptic number.

1871491 is a deficient number, since it is larger than the sum of its proper divisors (1).

1871491 is an equidigital number, since it uses as much as digits as its factorization.

1871491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2016, while the sum is 31.

The square root of 1871491 is about 1368.0244880849. The cubic root of 1871491 is about 123.2336317849.

The spelling of 1871491 in words is "one million, eight hundred seventy-one thousand, four hundred ninety-one".