172215450 has 96 divisors (see below), whose sum is σ = 517734720. Its totient is φ = 41745600.

The previous prime is 172215437. The next prime is 172215451. The reversal of 172215450 is 54512271.

It is a super-2 number, since 2×172215450² = 59316322437405000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (172215451) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 9052 + ... + 20648.

It is an arithmetic number, because the mean of its divisors is an integer number (5393070).

Almost surely, 2^172215450 is an apocalyptic number.

172215450 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 172215450, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (258867360).

172215450 is an abundant number, since it is smaller than the sum of its proper divisors (345519270).

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

172215450 is a wasteful number, since it uses less digits than its factorization.

172215450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11629 (or 11618 counting only the distinct ones).

The product of its (nonzero) digits is 2800, while the sum is 27.

The square root of 172215450 is about 13123.0884322251. The cubic root of 172215450 is about 556.3618855018.

The spelling of 172215450 in words is "one hundred seventy-two million, two hundred fifteen thousand, four hundred fifty".