40404204021 has 4 divisors (see below), whose sum is σ = 53872272032. Its totient is φ = 26936136012.

The previous prime is 40404204017. The next prime is 40404204023. The reversal of 40404204021 is 12040240404.

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 not a de Polignac number, because 40404204021 - 2² = 40404204017 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 (40404204023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6734034001 + ... + 6734034006.

It is an arithmetic number, because the mean of its divisors is an integer number (13468068008).

Almost surely, 2^40404204021 is an apocalyptic number.

It is an amenable number.

40404204021 is a deficient number, since it is larger than the sum of its proper divisors (13468068011).

40404204021 is a wasteful number, since it uses less digits than its factorization.

40404204021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13468068010.

The product of its (nonzero) digits is 1024, while the sum is 21.

Adding to 40404204021 its reverse (12040240404), we get a palindrome (52444444425).

The spelling of 40404204021 in words is "forty billion, four hundred four million, two hundred four thousand, twenty-one".