1011002120021 has 8 divisors (see below), whose sum is σ = 1012669030104. Its totient is φ = 1009336584960.

The previous prime is 1011002120017. The next prime is 1011002120041. The reversal of 1011002120021 is 1200212001101.

It can be written as a sum of positive squares in 4 ways, for example, as 262282258225 + 748719861796 = 512135^2 + 865286^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1011002120021 - 2² = 1011002120017 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1011002119984 and 1011002120011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1011002120041) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1133201 + ... + 1818281.

It is an arithmetic number, because the mean of its divisors is an integer number (126583628763).

Almost surely, 2^{1011002120021} is an apocalyptic number.

It is an amenable number.

1011002120021 is a deficient number, since it is larger than the sum of its proper divisors (1666910083).

1011002120021 is a wasteful number, since it uses less digits than its factorization.

1011002120021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 687511.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 1011002120021 its reverse (1200212001101), we get a palindrome (2211214121122).

The spelling of 1011002120021 in words is "one trillion, eleven billion, two million, one hundred twenty thousand, twenty-one".