20421004411405 has 16 divisors (see below), whose sum is σ = 27003947160960. Its totient is φ = 14729425720128.

The previous prime is 20421004411393. The next prime is 20421004411429. The reversal of 20421004411405 is 50411440012402.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 20421004411405 - 2⁵ = 20421004411373 is a prime.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 3653128585 + ... + 3653134174.

It is an arithmetic number, because the mean of its divisors is an integer number (1687746697560).

Almost surely, 2^{20421004411405} is an apocalyptic number.

It is an amenable number.

20421004411405 is a deficient number, since it is larger than the sum of its proper divisors (6582942749555).

20421004411405 is a wasteful number, since it uses less digits than its factorization.

20421004411405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7306262820.

The product of its (nonzero) digits is 5120, while the sum is 28.

Adding to 20421004411405 its reverse (50411440012402), we get a palindrome (70832444423807).

The spelling of 20421004411405 in words is "twenty trillion, four hundred twenty-one billion, four million, four hundred eleven thousand, four hundred five".