1137721 has 4 divisors (see below), whose sum is σ = 1225252. Its totient is φ = 1050192.

The previous prime is 1137707. The next prime is 1137733. The reversal of 1137721 is 1277311.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1277311 = 7 ⋅182473.

It can be written as a sum of positive squares in 2 ways, for example, as 115600 + 1022121 = 340^2 + 1011^2 .

It is not a de Polignac number, because 1137721 - 2⁹ = 1137209 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1137692 and 1137701.

It is not an unprimeable number, because it can be changed into a prime (1137781) 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, 43746 + ... + 43771.

It is an arithmetic number, because the mean of its divisors is an integer number (306313).

2^1137721 is an apocalyptic number.

It is an amenable number.

1137721 is a deficient number, since it is larger than the sum of its proper divisors (87531).

1137721 is an equidigital number, since it uses as much as digits as its factorization.

1137721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87530.

The product of its digits is 294, while the sum is 22.

The square root of 1137721 is about 1066.6400517513. The cubic root of 1137721 is about 104.3947338594.

The spelling of 1137721 in words is "one million, one hundred thirty-seven thousand, seven hundred twenty-one".