1020123221 has 4 divisors (see below), whose sum is σ = 1098594252. Its totient is φ = 941652192.

The previous prime is 1020123217. The next prime is 1020123257. The reversal of 1020123221 is 1223210201.

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: 1223210201 = 241 ⋅5075561.

It can be written as a sum of positive squares in 2 ways, for example, as 66178225 + 953944996 = 8135^2 + 30886^2 .

It is not a de Polignac number, because 1020123221 - 2² = 1020123217 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1020123196 and 1020123205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1020123121) 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, 39235496 + ... + 39235521.

It is an arithmetic number, because the mean of its divisors is an integer number (274648563).

Almost surely, 2^1020123221 is an apocalyptic number.

It is an amenable number.

1020123221 is a deficient number, since it is larger than the sum of its proper divisors (78471031).

1020123221 is an equidigital number, since it uses as much as digits as its factorization.

1020123221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78471030.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 1020123221 is about 31939.3678866693. The cubic root of 1020123221 is about 1006.6632429139.

Adding to 1020123221 its reverse (1223210201), we get a palindrome (2243333422).

The spelling of 1020123221 in words is "one billion, twenty million, one hundred twenty-three thousand, two hundred twenty-one".