172023426 has 40 divisors (see below), whose sum is σ = 387226620. Its totient is φ = 57078432.

The previous prime is 172023421. The next prime is 172023427. The reversal of 172023426 is 624320271.

172023426 is a nontrivial binomial coefficient, being equal to C(18549, 2).

It can be written as a sum of positive squares in 2 ways, for example, as 169130025 + 2893401 = 13005^2 + 1701^2 .

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

It is a self number, because there is not a number n which added to its sum of digits gives 172023426.

It is not an unprimeable number, because it can be changed into a prime (172023421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 34780 + ... + 39416.

Almost surely, 2^172023426 is an apocalyptic number.

172023426 is the 18548-th triangular number.

It is a practical number, because each smaller number is the sum of distinct divisors of 172023426, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (193613310).

172023426 is an abundant number, since it is smaller than the sum of its proper divisors (215203194).

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

172023426 is a wasteful number, since it uses less digits than its factorization.

172023426 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4880 (or 4871 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 27.

The square root of 172023426 is about 13115.7701260734. The cubic root of 172023426 is about 556.1550233667.

Adding to 172023426 its reverse (624320271), we get a palindrome (796343697).

The spelling of 172023426 in words is "one hundred seventy-two million, twenty-three thousand, four hundred twenty-six".