729018251661 has 8 divisors (see below), whose sum is σ = 1110884954944. Its totient is φ = 416581858080.

The previous prime is 729018251581. The next prime is 729018251681. The reversal of 729018251661 is 166152810927.

It is a happy number.

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

It is not a de Polignac number, because 729018251661 - 2¹⁰ = 729018250637 is a prime.

It is a super-2 number, since 2×729018251661² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 729018251661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (729018251681) 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, 17357577400 + ... + 17357577441.

It is an arithmetic number, because the mean of its divisors is an integer number (138860619368).

Almost surely, 2^729018251661 is an apocalyptic number.

It is an amenable number.

729018251661 is a deficient number, since it is larger than the sum of its proper divisors (381866703283).

729018251661 is a wasteful number, since it uses less digits than its factorization.

729018251661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34715154851.

The product of its (nonzero) digits is 362880, while the sum is 48.

The spelling of 729018251661 in words is "seven hundred twenty-nine billion, eighteen million, two hundred fifty-one thousand, six hundred sixty-one".