2121520 has 40 divisors (see below), whose sum is σ = 5151456. Its totient is φ = 811008.

The previous prime is 2121503. The next prime is 2121529. The reversal of 2121520 is 251212.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×2121520² = 9001694220800, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 2121520.

It is not an unprimeable number, because it can be changed into a prime (2121529) 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, 1264 + ... + 2416.

2^2121520 is an apocalyptic number.

2121520 is a gapful number since it is divisible by the number (20) 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 2121520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2575728).

2121520 is an abundant number, since it is smaller than the sum of its proper divisors (3029936).

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

2121520 is a wasteful number, since it uses less digits than its factorization.

2121520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1189 (or 1183 counting only the distinct ones).

The product of its (nonzero) digits is 40, while the sum is 13.

The square root of 2121520 is about 1456.5438544719. The cubic root of 2121520 is about 128.4938603253.

Adding to 2121520 its reverse (251212), we get a palindrome (2372732).

The spelling of 2121520 in words is "two million, one hundred twenty-one thousand, five hundred twenty".