729997920 has 480 divisors, whose sum is σ = 2810142720. Its totient is φ = 177914880.

The previous prime is 729997909. The next prime is 729997987. The reversal of 729997920 is 29799927.

It is a tau number, because it is divible by the number of its divisors (480).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 9240441 + ... + 9240519.

It is an arithmetic number, because the mean of its divisors is an integer number (5854464).

Almost surely, 2^729997920 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 729997920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1405071360).

729997920 is an abundant number, since it is smaller than the sum of its proper divisors (2080144800).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

729997920 is a wasteful number, since it uses less digits than its factorization.

729997920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160 (or 143 counting only the distinct ones).

The product of its (nonzero) digits is 1285956, while the sum is 54.

The square root of 729997920 is about 27018.4736800582. The cubic root of 729997920 is about 900.4104794234.

The spelling of 729997920 in words is "seven hundred twenty-nine million, nine hundred ninety-seven thousand, nine hundred twenty".