172720557885 has 16 divisors (see below), whose sum is σ = 276377894784. Its totient is φ = 92109296832.

The previous prime is 172720557859. The next prime is 172720557917. The reversal of 172720557885 is 588755027271.

It is not a de Polignac number, because 172720557885 - 2⁸ = 172720557629 is a prime.

It is a super-2 number, since 2×172720557885² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 347697 + ... + 682886.

It is an arithmetic number, because the mean of its divisors is an integer number (17273618424).

Almost surely, 2^172720557885 is an apocalyptic number.

172720557885 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

172720557885 is a deficient number, since it is larger than the sum of its proper divisors (103657336899).

172720557885 is a wasteful number, since it uses less digits than its factorization.

172720557885 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1041764.

The product of its (nonzero) digits is 10976000, while the sum is 57.

The spelling of 172720557885 in words is "one hundred seventy-two billion, seven hundred twenty million, five hundred fifty-seven thousand, eight hundred eighty-five".