1151721 has 12 divisors (see below), whose sum is σ = 1687348. Its totient is φ = 756864.

The previous prime is 1151713. The next prime is 1151729. The reversal of 1151721 is 1271511.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1151713) and next prime (1151729).

It can be written as a sum of positive squares in 2 ways, for example, as 275625 + 876096 = 525^2 + 936^2 .

It is not a de Polignac number, because 1151721 - 2³ = 1151713 is a prime.

It is a super-2 number, since 2×1151721² = 2652922523682, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1151694 and 1151703.

It is not an unprimeable number, because it can be changed into a prime (1151729) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 220 + ... + 1533.

2^1151721 is an apocalyptic number.

It is an amenable number.

1151721 is a deficient number, since it is larger than the sum of its proper divisors (535627).

1151721 is a wasteful number, since it uses less digits than its factorization.

1151721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1832 (or 1829 counting only the distinct ones).

The product of its digits is 70, while the sum is 18.

The square root of 1151721 is about 1073.1826498784. The cubic root of 1151721 is about 104.8211922743.

The spelling of 1151721 in words is "one million, one hundred fifty-one thousand, seven hundred twenty-one".