1016721 has 12 divisors (see below), whose sum is σ = 1479348. Its totient is φ = 672864.

The previous prime is 1016689. The next prime is 1016731. The reversal of 1016721 is 1276101.

1016721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 608400 + 408321 = 780^2 + 639^2 .

It is not a de Polignac number, because 1016721 - 2⁵ = 1016689 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1016694 and 1016703.

It is not an unprimeable number, because it can be changed into a prime (1016731) 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, 1231 + ... + 1883.

It is an arithmetic number, because the mean of its divisors is an integer number (123279).

2^1016721 is an apocalyptic number.

It is an amenable number.

1016721 is a deficient number, since it is larger than the sum of its proper divisors (462627).

1016721 is a wasteful number, since it uses less digits than its factorization.

1016721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 832 (or 829 counting only the distinct ones).

The product of its (nonzero) digits is 84, while the sum is 18.

The square root of 1016721 is about 1008.3258401925. The cubic root of 1016721 is about 100.5542886312.

The spelling of 1016721 in words is "one million, sixteen thousand, seven hundred twenty-one".