1020421110421 has 4 divisors (see below), whose sum is σ = 1020423894700. Its totient is φ = 1020418326144.

The previous prime is 1020421110419. The next prime is 1020421110439. The reversal of 1020421110421 is 1240111240201.

It is a happy number.

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 675248410225 + 345172700196 = 821735^2 + 587514^2 .

It is a cyclic number.

It is not a de Polignac number, because 1020421110421 - 2¹ = 1020421110419 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 (1020421110461) 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, 740826 + ... + 1609243.

It is an arithmetic number, because the mean of its divisors is an integer number (255105973675).

Almost surely, 2^{1020421110421} is an apocalyptic number.

It is an amenable number.

1020421110421 is a deficient number, since it is larger than the sum of its proper divisors (2784279).

1020421110421 is an equidigital number, since it uses as much as digits as its factorization.

1020421110421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2784278.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 1020421110421 its reverse (1240111240201), we get a palindrome (2260532350622).

It can be divided in two parts, 1020 and 421110421, that added together give a square (421111441 = 20521²).

The spelling of 1020421110421 in words is "one trillion, twenty billion, four hundred twenty-one million, one hundred ten thousand, four hundred twenty-one".