72173420 has 24 divisors (see below), whose sum is σ = 165343248. Its totient is φ = 26244800.

The previous prime is 72173399. The next prime is 72173441. The reversal of 72173420 is 2437127.

It is an interprime number because it is at equal distance from previous prime (72173399) and next prime (72173441).

It is a self number, because there is not a number n which added to its sum of digits gives 72173420.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 163811 + ... + 164250.

It is an arithmetic number, because the mean of its divisors is an integer number (6889302).

Almost surely, 2^72173420 is an apocalyptic number.

It is an amenable number.

72173420 is an abundant number, since it is smaller than the sum of its proper divisors (93169828).

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

72173420 is a wasteful number, since it uses less digits than its factorization.

72173420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 328081 (or 328079 counting only the distinct ones).

The product of its (nonzero) digits is 2352, while the sum is 26.

The square root of 72173420 is about 8495.4940998155. The cubic root of 72173420 is about 416.3505043378.

The spelling of 72173420 in words is "seventy-two million, one hundred seventy-three thousand, four hundred twenty".