172021740 has 96 divisors (see below), whose sum is σ = 531062784. Its totient is φ = 41256960.

The previous prime is 172021723. The next prime is 172021747. The reversal of 172021740 is 47120271.

172021740 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 172021740.

It is not an unprimeable number, because it can be changed into a prime (172021747) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 62677 + ... + 65363.

It is an arithmetic number, because the mean of its divisors is an integer number (5531904).

Almost surely, 2^172021740 is an apocalyptic number.

172021740 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 172021740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (265531392).

172021740 is an abundant number, since it is smaller than the sum of its proper divisors (359041044).

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

172021740 is a wasteful number, since it uses less digits than its factorization.

172021740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2807 (or 2805 counting only the distinct ones).

The product of its (nonzero) digits is 784, while the sum is 24.

The square root of 172021740 is about 13115.7058521454. The cubic root of 172021740 is about 556.1532064041.

The spelling of 172021740 in words is "one hundred seventy-two million, twenty-one thousand, seven hundred forty".