1611220 has 24 divisors (see below), whose sum is σ = 3644424. Its totient is φ = 594816.

The previous prime is 1611217. The next prime is 1611223. The reversal of 1611220 is 221161.

It is an interprime number because it is at equal distance from previous prime (1611217) and next prime (1611223).

It can be written as a sum of positive squares in 4 ways, for example, as 8464 + 1602756 = 92^2 + 1266^2 .

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a self number, because there is not a number n which added to its sum of digits gives 1611220.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1611223) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2839 + ... + 3358.

It is an arithmetic number, because the mean of its divisors is an integer number (151851).

2^1611220 is an apocalyptic number.

1611220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1611220 is an abundant number, since it is smaller than the sum of its proper divisors (2033204).

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

1611220 is a wasteful number, since it uses less digits than its factorization.

1611220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6219 (or 6217 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 13.

The square root of 1611220 is about 1269.3384103540. The cubic root of 1611220 is about 117.2334686028.

Adding to 1611220 its reverse (221161), we get a palindrome (1832381).

It can be divided in two parts, 16 and 11220, that added together give a square (11236 = 106²).

The spelling of 1611220 in words is "one million, six hundred eleven thousand, two hundred twenty".