1021805002 has 4 divisors (see below), whose sum is σ = 1532707506. Its totient is φ = 510902500.

The previous prime is 1021804997. The next prime is 1021805003. The reversal of 1021805002 is 2005081201.

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

It can be written as a sum of positive squares in only one way, i.e., 1019461041 + 2343961 = 31929^2 + 1531^2 .

It is a super-2 number, since 2×1021805002² = 2088170924224440008, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1021805003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 255451249 + ... + 255451252.

Almost surely, 2^1021805002 is an apocalyptic number.

1021805002 is a deficient number, since it is larger than the sum of its proper divisors (510902504).

1021805002 is an equidigital number, since it uses as much as digits as its factorization.

1021805002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 510902503.

The product of its (nonzero) digits is 160, while the sum is 19.

The square root of 1021805002 is about 31965.6847572518. The cubic root of 1021805002 is about 1007.2161361251.

Adding to 1021805002 its reverse (2005081201), we get a palindrome (3026886203).

The spelling of 1021805002 in words is "one billion, twenty-one million, eight hundred five thousand, two".