1002220021 has 4 divisors (see below), whose sum is σ = 1093330944. Its totient is φ = 911109100.

The previous prime is 1002220001. The next prime is 1002220033. The reversal of 1002220021 is 1200222001.

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 not a de Polignac number, because 1002220021 - 2⁷ = 1002219893 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1002220001) 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, 45555445 + ... + 45555466.

It is an arithmetic number, because the mean of its divisors is an integer number (273332736).

Almost surely, 2^1002220021 is an apocalyptic number.

1002220021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1002220021 is a deficient number, since it is larger than the sum of its proper divisors (91110923).

1002220021 is an equidigital number, since it uses as much as digits as its factorization.

1002220021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91110922.

The product of its (nonzero) digits is 16, while the sum is 10.

The square root of 1002220021 is about 31657.8587557655. The cubic root of 1002220021 is about 1000.7394600640.

Adding to 1002220021 its reverse (1200222001), we get a palindrome (2202442022).

The spelling of 1002220021 in words is "one billion, two million, two hundred twenty thousand, twenty-one".