1021220321 has 32 divisors (see below), whose sum is σ = 1180016640. Its totient is φ = 875289600.

The previous prime is 1021220293. The next prime is 1021220323. The reversal of 1021220321 is 1230221201.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1021220321 - 2⁶ = 1021220257 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1021220296 and 1021220305.

It is not an unprimeable number, because it can be changed into a prime (1021220323) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3882836 + ... + 3883098.

It is an arithmetic number, because the mean of its divisors is an integer number (36875520).

Almost surely, 2^1021220321 is an apocalyptic number.

1021220321 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1021220321 is a deficient number, since it is larger than the sum of its proper divisors (158796319).

1021220321 is a wasteful number, since it uses less digits than its factorization.

1021220321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 557.

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

The square root of 1021220321 is about 31956.5380008536. The cubic root of 1021220321 is about 1007.0239884074.

Adding to 1021220321 its reverse (1230221201), we get a palindrome (2251441522).

The spelling of 1021220321 in words is "one billion, twenty-one million, two hundred twenty thousand, three hundred twenty-one".