1020312221 has 4 divisors (see below), whose sum is σ = 1021246812. Its totient is φ = 1019377632.

The previous prime is 1020312211. The next prime is 1020312229. The reversal of 1020312221 is 1222130201.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 849722500 + 170589721 = 29150^2 + 13061^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1020312221 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1020312196 and 1020312205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1020312229) 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, 465656 + ... + 467841.

It is an arithmetic number, because the mean of its divisors is an integer number (255311703).

Almost surely, 2^1020312221 is an apocalyptic number.

It is an amenable number.

1020312221 is a deficient number, since it is larger than the sum of its proper divisors (934591).

1020312221 is an equidigital number, since it uses as much as digits as its factorization.

1020312221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 934590.

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

The square root of 1020312221 is about 31942.3264807058. The cubic root of 1020312221 is about 1006.7254078237.

Adding to 1020312221 its reverse (1222130201), we get a palindrome (2242442422).

The spelling of 1020312221 in words is "one billion, twenty million, three hundred twelve thousand, two hundred twenty-one".