1728723157 has 8 divisors (see below), whose sum is σ = 1975939200. Its totient is φ = 1481571024.

The previous prime is 1728723133. The next prime is 1728723169. The reversal of 1728723157 is 7513278271.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1728723157 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1728723107) 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, 82344 + ... + 101182.

It is an arithmetic number, because the mean of its divisors is an integer number (246992400).

Almost surely, 2^1728723157 is an apocalyptic number.

It is an amenable number.

1728723157 is a deficient number, since it is larger than the sum of its proper divisors (247216043).

1728723157 is a wasteful number, since it uses less digits than its factorization.

1728723157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31955.

The product of its digits is 164640, while the sum is 43.

The square root of 1728723157 is about 41577.9166986515. The cubic root of 1728723157 is about 1200.1673741075.

The spelling of 1728723157 in words is "one billion, seven hundred twenty-eight million, seven hundred twenty-three thousand, one hundred fifty-seven".