21663356122005 has 64 divisors (see below), whose sum is σ = 37370077704960. Its totient is φ = 10652915460096.

The previous prime is 21663356121991. The next prime is 21663356122061. The reversal of 21663356122005 is 50022165336612.

It is a happy number.

It is not a de Polignac number, because 21663356122005 - 2⁶ = 21663356121941 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 687426129 + ... + 687457641.

It is an arithmetic number, because the mean of its divisors is an integer number (583907464140).

Almost surely, 2^{21663356122005} is an apocalyptic number.

It is an amenable number.

21663356122005 is a deficient number, since it is larger than the sum of its proper divisors (15706721582955).

21663356122005 is a wasteful number, since it uses less digits than its factorization.

21663356122005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35430.

The product of its (nonzero) digits is 388800, while the sum is 42.

The spelling of 21663356122005 in words is "twenty-one trillion, six hundred sixty-three billion, three hundred fifty-six million, one hundred twenty-two thousand, five".