900021729 has 8 divisors (see below), whose sum is σ = 1238739712. Its totient is φ = 580659120.

The previous prime is 900021719. The next prime is 900021739. The reversal of 900021729 is 927120009.

It is an interprime number because it is at equal distance from previous prime (900021719) and next prime (900021739).

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

It is not a de Polignac number, because 900021729 - 2⁴ = 900021713 is a prime.

It is a super-2 number, since 2×900021729² = 1620078225344298882, 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 = 900021696 and 900021705.

It is not an unprimeable number, because it can be changed into a prime (900021719) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4838734 + ... + 4838919.

It is an arithmetic number, because the mean of its divisors is an integer number (154842464).

Almost surely, 2^900021729 is an apocalyptic number.

It is an amenable number.

900021729 is a deficient number, since it is larger than the sum of its proper divisors (338717983).

900021729 is a wasteful number, since it uses less digits than its factorization.

900021729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9677687.

The product of its (nonzero) digits is 2268, while the sum is 30.

The square root of 900021729 is about 30000.3621478141. The cubic root of 900021729 is about 965.4971545871.

The spelling of 900021729 in words is "nine hundred million, twenty-one thousand, seven hundred twenty-nine".