1010001220021 has 4 divisors (see below), whose sum is σ = 1010333788492. Its totient is φ = 1009668651552.

The previous prime is 1010001220003. The next prime is 1010001220037. The reversal of 1010001220021 is 1200221000101.

1010001220021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 900629470225 + 109371749796 = 949015^2 + 330714^2 .

It is a cyclic number.

It is not a de Polignac number, because 1010001220021 - 2⁷ = 1010001219893 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 (1010001220001) 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, 166279680 + ... + 166285753.

It is an arithmetic number, because the mean of its divisors is an integer number (252583447123).

Almost surely, 2^{1010001220021} is an apocalyptic number.

It is an amenable number.

1010001220021 is a deficient number, since it is larger than the sum of its proper divisors (332568471).

1010001220021 is an equidigital number, since it uses as much as digits as its factorization.

1010001220021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 332568470.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 1010001220021 its reverse (1200221000101), we get a palindrome (2210222220122).

The spelling of 1010001220021 in words is "one trillion, ten billion, one million, two hundred twenty thousand, twenty-one".