172439820 has 288 divisors, whose sum is σ = 658828800. Its totient is φ = 37340352.

The previous prime is 172439807. The next prime is 172439833. The reversal of 172439820 is 28934271.

It is an interprime number because it is at equal distance from previous prime (172439807) and next prime (172439833).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 9075771 + ... + 9075789.

It is an arithmetic number, because the mean of its divisors is an integer number (2287600).

Almost surely, 2^172439820 is an apocalyptic number.

172439820 is a gapful number since it is divisible by the number (10) 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 172439820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (329414400).

172439820 is an abundant number, since it is smaller than the sum of its proper divisors (486388980).

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

172439820 is an equidigital number, since it uses as much as digits as its factorization.

172439820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72 (or 36 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 172439820 is about 13131.6343232668. The cubic root of 172439820 is about 556.6033983736.

The spelling of 172439820 in words is "one hundred seventy-two million, four hundred thirty-nine thousand, eight hundred twenty".