1002120221 has 4 divisors (see below), whose sum is σ = 1002802944. Its totient is φ = 1001437500.

The previous prime is 1002120181. The next prime is 1002120227. The reversal of 1002120221 is 1220212001.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1220212001 = 23993 ⋅50857.

It is a cyclic number.

It is not a de Polignac number, because 1002120221 - 2⁶ = 1002120157 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1002120227) 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 3 ways as a sum of consecutive naturals, for example, 339155 + ... + 342096.

It is an arithmetic number, because the mean of its divisors is an integer number (250700736).

Almost surely, 2^1002120221 is an apocalyptic number.

It is an amenable number.

1002120221 is a deficient number, since it is larger than the sum of its proper divisors (682723).

1002120221 is an equidigital number, since it uses as much as digits as its factorization.

1002120221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 682722.

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 1002120221 is about 31656.2824886309. The cubic root of 1002120221 is about 1000.7062414389.

Adding to 1002120221 its reverse (1220212001), we get a palindrome (2222332222).

The spelling of 1002120221 in words is "one billion, two million, one hundred twenty thousand, two hundred twenty-one".