1200021002021 has 4 divisors (see below), whose sum is σ = 1200228516192. Its totient is φ = 1199813487852.

The previous prime is 1200021002017. The next prime is 1200021002027. The reversal of 1200021002021 is 1202001200021.

It is a happy number.

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 a cyclic number.

It is not a de Polignac number, because 1200021002021 - 2² = 1200021002017 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1200021001993 and 1200021002011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1200021002027) 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, 103748411 + ... + 103759976.

It is an arithmetic number, because the mean of its divisors is an integer number (300057129048).

Almost surely, 2^{1200021002021} is an apocalyptic number.

It is an amenable number.

1200021002021 is a deficient number, since it is larger than the sum of its proper divisors (207514171).

1200021002021 is an equidigital number, since it uses as much as digits as its factorization.

1200021002021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 207514170.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 1200021002021 its reverse (1202001200021), we get a palindrome (2402022202042).

The spelling of 1200021002021 in words is "one trillion, two hundred billion, twenty-one million, two thousand, twenty-one".