1001251 has 4 divisors (see below), whose sum is σ = 1004400. Its totient is φ = 998104.

The previous prime is 1001237. The next prime is 1001267. The reversal of 1001251 is 1521001.

1001251 = 406² + 407² + ... + 411².

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: 1521001 = 103 ⋅14767.

It is a cyclic number.

It is not a de Polignac number, because 1001251 - 2⁵ = 1001219 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1001291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1036 + ... + 1753.

It is an arithmetic number, because the mean of its divisors is an integer number (251100).

2^1001251 is an apocalyptic number.

1001251 is a deficient number, since it is larger than the sum of its proper divisors (3149).

1001251 is an equidigital number, since it uses as much as digits as its factorization.

1001251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3148.

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

The square root of 1001251 is about 1000.6253044971. The cubic root of 1001251 is about 100.0416826232.

Adding to 1001251 its reverse (1521001), we get a palindrome (2522252).

The spelling of 1001251 in words is "one million, one thousand, two hundred fifty-one".