21135858257738 has 16 divisors (see below), whose sum is σ = 36233346114240. Its totient is φ = 9058113406656.

The previous prime is 21135858257707. The next prime is 21135858257777. The reversal of 21135858257738 is 83775285853112.

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, 8114228 + ... + 10397711.

It is an arithmetic number, because the mean of its divisors is an integer number (2264584132140).

Almost surely, 2^{21135858257738} is an apocalyptic number.

21135858257738 is a deficient number, since it is larger than the sum of its proper divisors (15097487856502).

21135858257738 is a wasteful number, since it uses less digits than its factorization.

21135858257738 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18593501.

The product of its digits is 112896000, while the sum is 65.

The spelling of 21135858257738 in words is "twenty-one trillion, one hundred thirty-five billion, eight hundred fifty-eight million, two hundred fifty-seven thousand, seven hundred thirty-eight".