11521001 has 4 divisors (see below), whose sum is σ = 11564100. Its totient is φ = 11477904.

The previous prime is 11520991. The next prime is 11521007. The reversal of 11521001 is 10012511.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 10012511 = 29 ⋅345259.

It can be written as a sum of positive squares in 2 ways, for example, as 4734976 + 6786025 = 2176^2 + 2605^2 .

It is a cyclic number.

It is not a de Polignac number, because 11521001 - 2¹⁸ = 11258857 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11521007) 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, 21146 + ... + 21683.

It is an arithmetic number, because the mean of its divisors is an integer number (2891025).

Almost surely, 2^11521001 is an apocalyptic number.

It is an amenable number.

11521001 is a deficient number, since it is larger than the sum of its proper divisors (43099).

11521001 is an equidigital number, since it uses as much as digits as its factorization.

11521001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43098.

The product of its (nonzero) digits is 10, while the sum is 11.

The square root of 11521001 is about 3394.2600077189. The cubic root of 11521001 is about 225.8551882494.

Adding to 11521001 its reverse (10012511), we get a palindrome (21533512).

The spelling of 11521001 in words is "eleven million, five hundred twenty-one thousand, one".