1321520 has 20 divisors (see below), whose sum is σ = 3072720. Its totient is φ = 528576.

The previous prime is 1321517. The next prime is 1321549. The reversal of 1321520 is 251231.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (20).

It is a super-2 number, since 2×1321520² = 3492830220800, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1321495 and 1321504.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8180 + ... + 8339.

It is an arithmetic number, because the mean of its divisors is an integer number (153636).

2^1321520 is an apocalyptic number.

1321520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1321520 is an abundant number, since it is smaller than the sum of its proper divisors (1751200).

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

1321520 is a wasteful number, since it uses less digits than its factorization.

1321520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16532 (or 16526 counting only the distinct ones).

The product of its (nonzero) digits is 60, while the sum is 14.

The square root of 1321520 is about 1149.5738340794. The cubic root of 1321520 is about 109.7382204829.

Adding to 1321520 its reverse (251231), we get a palindrome (1572751).

The spelling of 1321520 in words is "one million, three hundred twenty-one thousand, five hundred twenty".