16509252 has 72 divisors (see below), whose sum is σ = 42159936. Its totient is φ = 5023296.

The previous prime is 16509247. The next prime is 16509257. The reversal of 16509252 is 25290561.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (16509247) and next prime (16509257).

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (16509257) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 160233 + ... + 160335.

Almost surely, 2^16509252 is an apocalyptic number.

16509252 is a gapful number since it is divisible by the number (12) 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 16509252, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21079968).

16509252 is an abundant number, since it is smaller than the sum of its proper divisors (25650684).

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

16509252 is a wasteful number, since it uses less digits than its factorization.

16509252 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185 (or 164 counting only the distinct ones).

The product of its (nonzero) digits is 5400, while the sum is 30.

The square root of 16509252 is about 4063.1578851923. The cubic root of 16509252 is about 254.6297433136.

It can be divided in two parts, 16509 and 252, that added together give a palindrome (16761).

The spelling of 16509252 in words is "sixteen million, five hundred nine thousand, two hundred fifty-two".