1021729 has 8 divisors (see below), whose sum is σ = 1101312. Its totient is φ = 945120.

The previous prime is 1021711. The next prime is 1021747. The reversal of 1021729 is 9271201.

It is an interprime number because it is at equal distance from previous prime (1021711) and next prime (1021747).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1021729 - 2⁵ = 1021697 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a nialpdrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021759) 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, 4 + ... + 1429.

It is an arithmetic number, because the mean of its divisors is an integer number (137664).

2^1021729 is an apocalyptic number.

It is an amenable number.

1021729 is a deficient number, since it is larger than the sum of its proper divisors (79583).

1021729 is a wasteful number, since it uses less digits than its factorization.

1021729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1487.

The product of its (nonzero) digits is 252, while the sum is 22.

The square root of 1021729 is about 1010.8061139506. The cubic root of 1021729 is about 100.7191163213.

The spelling of 1021729 in words is "one million, twenty-one thousand, seven hundred twenty-nine".