1275721 has 4 divisors (see below), whose sum is σ = 1302912. Its totient is φ = 1248532.

The previous prime is 1275719. The next prime is 1275737.

It is a happy number.

1275721 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1275721 - 2¹ = 1275719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1275751) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13525 + ... + 13618.

It is an arithmetic number, because the mean of its divisors is an integer number (325728).

2^1275721 is an apocalyptic number.

It is an amenable number.

1275721 is a deficient number, since it is larger than the sum of its proper divisors (27191).

1275721 is an equidigital number, since it uses as much as digits as its factorization.

1275721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27190.

The product of its digits is 980, while the sum is 25.

The square root of 1275721 is about 1129.4781981074. The cubic root of 1275721 is about 108.4555800812.

The spelling of 1275721 in words is "one million, two hundred seventy-five thousand, seven hundred twenty-one".