1271720 has 16 divisors (see below), whose sum is σ = 2861460. Its totient is φ = 508672.

The previous prime is 1271717. The next prime is 1271731. The reversal of 1271720 is 271721.

It can be written as a sum of positive squares in 2 ways, for example, as 1267876 + 3844 = 1126^2 + 62^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 1271692 and 1271701.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 15857 + ... + 15936.

2^1271720 is an apocalyptic number.

1271720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1271720 is an abundant number, since it is smaller than the sum of its proper divisors (1589740).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1271720 is a wasteful number, since it uses less digits than its factorization.

1271720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31804 (or 31800 counting only the distinct ones).

The product of its (nonzero) digits is 196, while the sum is 20.

The square root of 1271720 is about 1127.7056353499. The cubic root of 1271720 is about 108.3420795043.

Subtracting from 1271720 its reverse (271721), we obtain a palindrome (999999).

It can be divided in two parts, 1271 and 720, that added together give a palindrome (1991).

The spelling of 1271720 in words is "one million, two hundred seventy-one thousand, seven hundred twenty".