1020231221 has 2 divisors, whose sum is σ = 1020231222. Its totient is φ = 1020231220.

The previous prime is 1020231203. The next prime is 1020231257. The reversal of 1020231221 is 1221320201.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 578643025 + 441588196 = 24055^2 + 21014^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1020231221 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1020231196 and 1020231205.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1020231271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510115610 + 510115611.

It is an arithmetic number, because the mean of its divisors is an integer number (510115611).

Almost surely, 2^1020231221 is an apocalyptic number.

It is an amenable number.

1020231221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1020231221 is an equidigital number, since it uses as much as digits as its factorization.

1020231221 is an evil number, because the sum of its binary digits is even.

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

The square root of 1020231221 is about 31941.0585453895. The cubic root of 1020231221 is about 1006.6987666596.

Adding to 1020231221 its reverse (1221320201), we get a palindrome (2241551422).

The spelling of 1020231221 in words is "one billion, twenty million, two hundred thirty-one thousand, two hundred twenty-one".