1250021 has 2 divisors, whose sum is σ = 1250022.
Its totient is φ = 1250020.
The previous prime is 1250009. The next prime is 1250023. The reversal of 1250021 is 1200521.
Adding to 1250021 its reverse (1200521), we get a palindrome (2450542).
It can be divided in two parts, 12500 and 21, that added together give a palindrome (12521).
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 1240996 + 9025 = 1114^2 + 95^2
It is a cyclic number.
It is a de Polignac number, because none of the positive numbers 2k-1250021 is a prime.
Together with 1250023, it forms a pair of twin primes.
It is a Chen prime.
It is a junction number, because it is equal to n+sod(n) for n = 1249984 and 1250011.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (1250023) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 625010 + 625011.
It is an arithmetic number, because the mean of its divisors is an integer number (625011).
21250021 is an apocalyptic number.
It is an amenable number.
1250021 is a deficient number, since it is larger than the sum of its proper divisors (1).
1250021 is an equidigital number, since it uses as much as digits as its factorization.
1250021 is an evil number, because the sum of its binary digits is even.
The product of its (nonzero) digits is 20, while the sum is 11.
The square root of 1250021 is about 1118.0433801960.
The cubic root of 1250021 is about 107.7223377399.
The spelling of 1250021 in words is "one million, two hundred fifty thousand, twenty-one".