21351506636026 has 16 divisors (see below), whose sum is σ = 36607782942720. Its totient is φ = 9149345666640.

The previous prime is 21351506635999. The next prime is 21351506636071. The reversal of 21351506636026 is 62063660515312.

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, 108234145 + ... + 108431236.

It is an arithmetic number, because the mean of its divisors is an integer number (2287986433920).

Almost surely, 2^{21351506636026} is an apocalyptic number.

21351506636026 is a deficient number, since it is larger than the sum of its proper divisors (15256276306694).

21351506636026 is a wasteful number, since it uses less digits than its factorization.

21351506636026 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 216672429.

The product of its (nonzero) digits is 1166400, while the sum is 46.

The spelling of 21351506636026 in words is "twenty-one trillion, three hundred fifty-one billion, five hundred six million, six hundred thirty-six thousand, twenty-six".