1271990 has 16 divisors (see below), whose sum is σ = 2302560. Its totient is φ = 505920.

The previous prime is 1271987. The next prime is 1271999. The reversal of 1271990 is 991721.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1271999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2906 + ... + 3314.

It is an arithmetic number, because the mean of its divisors is an integer number (143910).

2^1271990 is an apocalyptic number.

1271990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1271990 is a deficient number, since it is larger than the sum of its proper divisors (1030570).

1271990 is a wasteful number, since it uses less digits than its factorization.

1271990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 727.

The product of its (nonzero) digits is 1134, while the sum is 29.

The square root of 1271990 is about 1127.8253410879. The cubic root of 1271990 is about 108.3497463627.

The spelling of 1271990 in words is "one million, two hundred seventy-one thousand, nine hundred ninety".