729999781 has 8 divisors (see below), whose sum is σ = 845714624. Its totient is φ = 617142240.

The previous prime is 729999763. The next prime is 729999797. The reversal of 729999781 is 187999927.

729999781 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 729999781 - 2⁷ = 729999653 is a prime.

It is a super-2 number, since 2×729999781² = 1065799360520095922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (729999701) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 713775 + ... + 714796.

It is an arithmetic number, because the mean of its divisors is an integer number (105714328).

Almost surely, 2^729999781 is an apocalyptic number.

It is an amenable number.

729999781 is a deficient number, since it is larger than the sum of its proper divisors (115714843).

729999781 is a wasteful number, since it uses less digits than its factorization.

729999781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1428651.

The product of its digits is 5143824, while the sum is 61.

The square root of 729999781 is about 27018.5081194355. The cubic root of 729999781 is about 900.4112445682.

The spelling of 729999781 in words is "seven hundred twenty-nine million, nine hundred ninety-nine thousand, seven hundred eighty-one".