21351108637118 has 16 divisors (see below), whose sum is σ = 34510992262656. Its totient is φ = 9848432161440.

The previous prime is 21351108637099. The next prime is 21351108637121. The reversal of 21351108637118 is 81173680115312.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 246858893 + ... + 246945368.

It is an arithmetic number, because the mean of its divisors is an integer number (2156937016416).

Almost surely, 2^{21351108637118} is an apocalyptic number.

21351108637118 is a deficient number, since it is larger than the sum of its proper divisors (13159883625538).

21351108637118 is a wasteful number, since it uses less digits than its factorization.

21351108637118 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 493805939.

The product of its (nonzero) digits is 241920, while the sum is 47.

The spelling of 21351108637118 in words is "twenty-one trillion, three hundred fifty-one billion, one hundred eight million, six hundred thirty-seven thousand, one hundred eighteen".