172137420 has 384 divisors, whose sum is σ = 686407680. Its totient is φ = 34836480.

The previous prime is 172137409. The next prime is 172137457. The reversal of 172137420 is 24731271.

It is a happy number.

172137420 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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

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 127 ways as a sum of consecutive naturals, for example, 1523284 + ... + 1523396.

It is an arithmetic number, because the mean of its divisors is an integer number (1787520).

Almost surely, 2^172137420 is an apocalyptic number.

172137420 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 172137420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (343203840).

172137420 is an abundant number, since it is smaller than the sum of its proper divisors (514270260).

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

172137420 is a wasteful number, since it uses less digits than its factorization.

172137420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 182 (or 174 counting only the distinct ones).

The product of its (nonzero) digits is 2352, while the sum is 27.

The square root of 172137420 is about 13120.1150909586. The cubic root of 172137420 is about 556.2778445010.

Adding to 172137420 its reverse (24731271), we get a palindrome (196868691).

The spelling of 172137420 in words is "one hundred seventy-two million, one hundred thirty-seven thousand, four hundred twenty".