16587220 has 48 divisors (see below), whose sum is σ = 37876608. Its totient is φ = 6065280.

The previous prime is 16587187. The next prime is 16587227. The reversal of 16587220 is 2278561.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16587227) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 33817 + ... + 34303.

It is an arithmetic number, because the mean of its divisors is an integer number (789096).

Almost surely, 2^16587220 is an apocalyptic number.

16587220 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 16587220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18938304).

16587220 is an abundant number, since it is smaller than the sum of its proper divisors (21289388).

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

16587220 is a wasteful number, since it uses less digits than its factorization.

16587220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 640 (or 638 counting only the distinct ones).

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 16587220 is about 4072.7410916973. The cubic root of 16587220 is about 255.0299593148.

It can be divided in two parts, 16587 and 220, that added together give a 5-th power (16807 = 7⁵).

The spelling of 16587220 in words is "sixteen million, five hundred eighty-seven thousand, two hundred twenty".