1021345505 has 4 divisors (see below), whose sum is σ = 1225614612. Its totient is φ = 817076400.

The previous prime is 1021345487. The next prime is 1021345517. The reversal of 1021345505 is 5055431201.

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 278455969 + 742889536 = 16687^2 + 27256^2 .

It is not a de Polignac number, because 1021345505 - 2¹⁸ = 1021083361 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

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, 102134546 + ... + 102134555.

It is an arithmetic number, because the mean of its divisors is an integer number (306403653).

Almost surely, 2^1021345505 is an apocalyptic number.

It is an amenable number.

1021345505 is a deficient number, since it is larger than the sum of its proper divisors (204269107).

1021345505 is an equidigital number, since it uses as much as digits as its factorization.

1021345505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204269106.

The product of its (nonzero) digits is 3000, while the sum is 26.

The square root of 1021345505 is about 31958.4966010606. The cubic root of 1021345505 is about 1007.0651346510.

Adding to 1021345505 its reverse (5055431201), we get a palindrome (6076776706).

The spelling of 1021345505 in words is "one billion, twenty-one million, three hundred forty-five thousand, five hundred five".