1020420321 has 4 divisors (see below), whose sum is σ = 1360560432. Its totient is φ = 680280212.

The previous prime is 1020420263. The next prime is 1020420329. The reversal of 1020420321 is 1230240201.

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.

It is a cyclic number.

It is not a de Polignac number, because 1020420321 - 2¹⁰ = 1020419297 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1020420321.

It is not an unprimeable number, because it can be changed into a prime (1020420329) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 170070051 + ... + 170070056.

It is an arithmetic number, because the mean of its divisors is an integer number (340140108).

Almost surely, 2^1020420321 is an apocalyptic number.

It is an amenable number.

1020420321 is a deficient number, since it is larger than the sum of its proper divisors (340140111).

1020420321 is an equidigital number, since it uses as much as digits as its factorization.

1020420321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 340140110.

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 1020420321 is about 31944.0185480788. The cubic root of 1020420321 is about 1006.7609600698.

Adding to 1020420321 its reverse (1230240201), we get a palindrome (2250660522).

The spelling of 1020420321 in words is "one billion, twenty million, four hundred twenty thousand, three hundred twenty-one".