172738939820 has 24 divisors (see below), whose sum is σ = 362802202224. Its totient is φ = 69085970496.

The previous prime is 172738939783. The next prime is 172738939823. The reversal of 172738939820 is 28939837271.

It is a self number, because there is not a number n which added to its sum of digits gives 172738939820.

It is not an unprimeable number, because it can be changed into a prime (172738939823) 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, 451982 + ... + 741461.

It is an arithmetic number, because the mean of its divisors is an integer number (15116758426).

Almost surely, 2^172738939820 is an apocalyptic number.

172738939820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

172738939820 is an abundant number, since it is smaller than the sum of its proper divisors (190063262404).

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

172738939820 is a wasteful number, since it uses less digits than its factorization.

172738939820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1200689 (or 1200687 counting only the distinct ones).

The product of its (nonzero) digits is 9144576, while the sum is 59.

The spelling of 172738939820 in words is "one hundred seventy-two billion, seven hundred thirty-eight million, nine hundred thirty-nine thousand, eight hundred twenty".