1621120 has 64 divisors (see below), whose sum is σ = 4131000. Its totient is φ = 606208.

The previous prime is 1621097. The next prime is 1621127. The reversal of 1621120 is 211261.

It can be written as a sum of positive squares in 4 ways, for example, as 1201216 + 419904 = 1096^2 + 648^2 .

It is a tau number, because it is divible by the number of its divisors (64).

It is a self number, because there is not a number n which added to its sum of digits gives 1621120.

It is not an unprimeable number, because it can be changed into a prime (1621127) 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, 10806 + ... + 10954.

2^1621120 is an apocalyptic number.

1621120 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 1621120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2065500).

1621120 is an abundant number, since it is smaller than the sum of its proper divisors (2509880).

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

1621120 is a wasteful number, since it uses less digits than its factorization.

1621120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185 (or 173 counting only the distinct ones).

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

The square root of 1621120 is about 1273.2321076693. The cubic root of 1621120 is about 117.4730887517.

Adding to 1621120 its reverse (211261), we get a palindrome (1832381).

The spelling of 1621120 in words is "one million, six hundred twenty-one thousand, one hundred twenty".