1001521 has 4 divisors (see below), whose sum is σ = 1060452. Its totient is φ = 942592.

The previous prime is 1001501. The next prime is 1001527. The reversal of 1001521 is 1251001.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1251001 = 73 ⋅17137.

It can be written as a sum of positive squares in 2 ways, for example, as 746496 + 255025 = 864^2 + 505^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1001521 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1001498 and 1001507.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1001527) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29440 + ... + 29473.

It is an arithmetic number, because the mean of its divisors is an integer number (265113).

2^1001521 is an apocalyptic number.

It is an amenable number.

1001521 is a deficient number, since it is larger than the sum of its proper divisors (58931).

1001521 is an equidigital number, since it uses as much as digits as its factorization.

1001521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58930.

The product of its (nonzero) digits is 10, while the sum is 10.

The square root of 1001521 is about 1000.7602110396. The cubic root of 1001521 is about 100.0506743168.

Adding to 1001521 its reverse (1251001), we get a palindrome (2252522).

It can be divided in two parts, 100 and 1521, that multiplied together give a square (152100 = 390²).

The spelling of 1001521 in words is "one million, one thousand, five hundred twenty-one".