1021200120021 has 8 divisors (see below), whose sum is σ = 1361612368480. Its totient is φ = 680793975792.

The previous prime is 1021200120019. The next prime is 1021200120071. The reversal of 1021200120021 is 1200210021201.

1021200120021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 1021200120021 - 2¹ = 1021200120019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1021200119979 and 1021200120006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021200120001) 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, 1120291 + ... + 1815888.

It is an arithmetic number, because the mean of its divisors is an integer number (170201546060).

Almost surely, 2^{1021200120021} is an apocalyptic number.

It is an amenable number.

1021200120021 is a deficient number, since it is larger than the sum of its proper divisors (340412248459).

1021200120021 is a wasteful number, since it uses less digits than its factorization.

1021200120021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3052115.

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 1021200120021 its reverse (1200210021201), we get a palindrome (2221410141222).

The spelling of 1021200120021 in words is "one trillion, twenty-one billion, two hundred million, one hundred twenty thousand, twenty-one".