40404029021 has 2 divisors, whose sum is σ = 40404029022. Its totient is φ = 40404029020.

The previous prime is 40404028981. The next prime is 40404029051. The reversal of 40404029021 is 12092040404.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 39317337796 + 1086691225 = 198286^2 + 32965^2 .

It is a cyclic number.

It is not a de Polignac number, because 40404029021 - 2¹⁰ = 40404027997 is a prime.

It is a super-2 number, since 2×40404029021² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40404029051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20202014510 + 20202014511.

It is an arithmetic number, because the mean of its divisors is an integer number (20202014511).

Almost surely, 2^40404029021 is an apocalyptic number.

It is an amenable number.

40404029021 is a deficient number, since it is larger than the sum of its proper divisors (1).

40404029021 is an equidigital number, since it uses as much as digits as its factorization.

40404029021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 26.

Adding to 40404029021 its reverse (12092040404), we get a palindrome (52496069425).

The spelling of 40404029021 in words is "forty billion, four hundred four million, twenty-nine thousand, twenty-one".