172821798072 has 512 divisors, whose sum is σ = 626658508800. Its totient is φ = 42819840000.

The previous prime is 172821798053. The next prime is 172821798101. The reversal of 172821798072 is 270897128271.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 36604672 + ... + 36609392.

It is an arithmetic number, because the mean of its divisors is an integer number (1223942400).

Almost surely, 2^172821798072 is an apocalyptic number.

172821798072 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 172821798072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (313329254400).

172821798072 is an abundant number, since it is smaller than the sum of its proper divisors (453836710728).

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

172821798072 is a wasteful number, since it uses less digits than its factorization.

172821798072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4856 (or 4846 counting only the distinct ones).

The product of its (nonzero) digits is 1580544, while the sum is 54.

The spelling of 172821798072 in words is "one hundred seventy-two billion, eight hundred twenty-one million, seven hundred ninety-eight thousand, seventy-two".