42031121021 has 4 divisors (see below), whose sum is σ = 42033457344. Its totient is φ = 42028784700.

The previous prime is 42031120969. The next prime is 42031121039. The reversal of 42031121021 is 12012113024.

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 42031121021 - 2¹⁰ = 42031119997 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 (42031121051) 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, 1140965 + ... + 1177226.

It is an arithmetic number, because the mean of its divisors is an integer number (10508364336).

Almost surely, 2^42031121021 is an apocalyptic number.

It is an amenable number.

42031121021 is a deficient number, since it is larger than the sum of its proper divisors (2336323).

42031121021 is a wasteful number, since it uses less digits than its factorization.

42031121021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2336322.

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 42031121021 its reverse (12012113024), we get a palindrome (54043234045).

The spelling of 42031121021 in words is "forty-two billion, thirty-one million, one hundred twenty-one thousand, twenty-one".