101001221 has 4 divisors (see below), whose sum is σ = 101065452.
Its totient is φ = 100936992.
The previous prime is 101001217. The next prime is 101001331. The reversal of 101001221 is 122100101.
It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 122100101 = 61 ⋅2001641.
It can be written as a sum of positive squares in 2 ways, for example, as 25502500 + 75498721 = 5050^2 + 8689^2
It is a cyclic number.
It is not a de Polignac number, because 101001221 - 22 = 101001217 is a prime.
It is a Duffinian number.
101001221 is a modest number, since divided by 1221 gives 101 as remainder.
It is a junction number, because it is equal to n+sod(n) for n = 101001199 and 101001208.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (101001521) 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, 29696 + ... + 32921.
It is an arithmetic number, because the mean of its divisors is an integer number (25266363).
Almost surely, 2101001221 is an apocalyptic number.
It is an amenable number.
101001221 is a deficient number, since it is larger than the sum of its proper divisors (64231).
101001221 is an equidigital number, since it uses as much as digits as its factorization.
101001221 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 64230.
The product of its (nonzero) digits is 4, while the sum is 8.
The square root of 101001221 is about 10049.9363679578.
The cubic root of 101001221 is about 465.7028274093.
Adding to 101001221 its reverse (122100101), we get a palindrome (223101322).
It can be divided in two parts, 101001 and 221, that multiplied together give a triangular number (22321221 = T6681).
The spelling of 101001221 in words is "one hundred one million, one thousand, two hundred twenty-one".