16500420 has 108 divisors (see below), whose sum is σ = 52312260. Its totient is φ = 4209408.

The previous prime is 16500413. The next prime is 16500427. The reversal of 16500420 is 2400561.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (16500413) and next prime (16500427).

It can be written as a sum of positive squares in 6 ways, for example, as 49284 + 16451136 = 222^2 + 4056^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 16500393 and 16500402.

It is not an unprimeable number, because it can be changed into a prime (16500427) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 151326 + ... + 151434.

Almost surely, 2^16500420 is an apocalyptic number.

16500420 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 16500420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26156130).

16500420 is an abundant number, since it is smaller than the sum of its proper divisors (35811840).

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

16500420 is a wasteful number, since it uses less digits than its factorization.

16500420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 182 (or 148 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 16500420 is about 4062.0709004152. The cubic root of 16500420 is about 254.5843285558.

Adding to 16500420 its reverse (2400561), we get a palindrome (18900981).

The spelling of 16500420 in words is "sixteen million, five hundred thousand, four hundred twenty".