1142721 has 8 divisors (see below), whose sum is σ = 1692960. Its totient is φ = 761796.

The previous prime is 1142707. The next prime is 1142737. The reversal of 1142721 is 1272411.

It is not a de Polignac number, because 1142721 - 2⁷ = 1142593 is a prime.

It is a super-2 number, since 2×1142721² = 2611622567682, which contains 22 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1142694 and 1142703.

It is not an unprimeable number, because it can be changed into a prime (1142021) 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, 21135 + ... + 21188.

It is an arithmetic number, because the mean of its divisors is an integer number (211620).

2^1142721 is an apocalyptic number.

It is an amenable number.

1142721 is a deficient number, since it is larger than the sum of its proper divisors (550239).

1142721 is an equidigital number, since it uses as much as digits as its factorization.

1142721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42332 (or 42326 counting only the distinct ones).

The product of its digits is 112, while the sum is 18.

The square root of 1142721 is about 1068.9812907624. The cubic root of 1142721 is about 104.5474399806.

The spelling of 1142721 in words is "one million, one hundred forty-two thousand, seven hundred twenty-one".