1001251521 has 12 divisors (see below), whose sum is σ = 1446553680. Its totient is φ = 667361880.

The previous prime is 1001251507. The next prime is 1001251523. The reversal of 1001251521 is 1251521001.

It is a de Polignac number, because none of the positive numbers 2^k-1001251521 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1001251494 and 1001251503.

It is not an unprimeable number, because it can be changed into a prime (1001251523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 52806 + ... + 69216.

It is an arithmetic number, because the mean of its divisors is an integer number (120546140).

Almost surely, 2^1001251521 is an apocalyptic number.

It is an amenable number.

1001251521 is a deficient number, since it is larger than the sum of its proper divisors (445302159).

1001251521 is a wasteful number, since it uses less digits than its factorization.

1001251521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23196 (or 23193 counting only the distinct ones).

The product of its (nonzero) digits is 100, while the sum is 18.

The square root of 1001251521 is about 31642.5586986893. The cubic root of 1001251521 is about 1000.4169997537.

Adding to 1001251521 its reverse (1251521001), we get a palindrome (2252772522).

The spelling of 1001251521 in words is "one billion, one million, two hundred fifty-one thousand, five hundred twenty-one".