16261220 has 12 divisors (see below), whose sum is σ = 34148604. Its totient is φ = 6504480.

The previous prime is 16261211. The next prime is 16261237. The reversal of 16261220 is 2216261.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 6885376 + 9375844 = 2624^2 + 3062^2 .

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 813061 = 16261220 / (1 + 6 + 2 + 6 + 1 + 2 + 2 + 0).

It is a junction number, because it is equal to n+sod(n) for n = 16261192 and 16261201.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 406511 + ... + 406550.

It is an arithmetic number, because the mean of its divisors is an integer number (2845717).

Almost surely, 2^16261220 is an apocalyptic number.

16261220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

16261220 is an abundant number, since it is smaller than the sum of its proper divisors (17887384).

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

16261220 is a wasteful number, since it uses less digits than its factorization.

16261220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 813070 (or 813068 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 16261220 is about 4032.5203037307. The cubic root of 16261220 is about 253.3481331766.

Adding to 16261220 its reverse (2216261), we get a palindrome (18477481).

The spelling of 16261220 in words is "sixteen million, two hundred sixty-one thousand, two hundred twenty".