40405000421 has 2 divisors, whose sum is σ = 40405000422. Its totient is φ = 40405000420.

The previous prime is 40405000417. The next prime is 40405000451. The reversal of 40405000421 is 12400050404.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 40005600196 + 399400225 = 200014^2 + 19985^2 .

It is a cyclic number.

It is not a de Polignac number, because 40405000421 - 2² = 40405000417 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 40405000393 and 40405000402.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40405000451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20202500210 + 20202500211.

It is an arithmetic number, because the mean of its divisors is an integer number (20202500211).

Almost surely, 2^40405000421 is an apocalyptic number.

It is an amenable number.

40405000421 is a deficient number, since it is larger than the sum of its proper divisors (1).

40405000421 is an equidigital number, since it uses as much as digits as its factorization.

40405000421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 640, while the sum is 20.

Adding to 40405000421 its reverse (12400050404), we get a palindrome (52805050825).

The spelling of 40405000421 in words is "forty billion, four hundred five million, four hundred twenty-one", and thus it is an aban number.