40042444021 has 4 divisors (see below), whose sum is σ = 41783419872. Its totient is φ = 38301468172.

The previous prime is 40042444019. The next prime is 40042444027. The reversal of 40042444021 is 12044424004.

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 40042444021 - 2¹ = 40042444019 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 (40042444027) 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, 870487891 + ... + 870487936.

It is an arithmetic number, because the mean of its divisors is an integer number (10445854968).

Almost surely, 2^40042444021 is an apocalyptic number.

It is an amenable number.

40042444021 is a deficient number, since it is larger than the sum of its proper divisors (1740975851).

40042444021 is a wasteful number, since it uses less digits than its factorization.

40042444021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1740975850.

The product of its (nonzero) digits is 4096, while the sum is 25.

Adding to 40042444021 its reverse (12044424004), we get a palindrome (52086868025).

The spelling of 40042444021 in words is "forty billion, forty-two million, four hundred forty-four thousand, twenty-one".