729621 has 16 divisors (see below), whose sum is σ = 1101120. Its totient is φ = 477360.

The previous prime is 729613. The next prime is 729637. The reversal of 729621 is 126927.

It is not a de Polignac number, because 729621 - 2³ = 729613 is a prime.

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (729601) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1426 + ... + 1868.

It is an arithmetic number, because the mean of its divisors is an integer number (68820).

2⁷²⁹⁶²¹ is an apocalyptic number.

It is an amenable number.

729621 is a deficient number, since it is larger than the sum of its proper divisors (371499).

729621 is a wasteful number, since it uses less digits than its factorization.

729621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 513 (or 507 counting only the distinct ones).

The product of its digits is 1512, while the sum is 27.

The square root of 729621 is about 854.1785527628. The cubic root of 729621 is about 90.0255483025.

The spelling of 729621 in words is "seven hundred twenty-nine thousand, six hundred twenty-one".