21539342154239 has 24 divisors (see below), whose sum is σ = 27712631515968. Its totient is φ = 16581519097920.

The previous prime is 21539342154227. The next prime is 21539342154241. The reversal of 21539342154239 is 93245124393512.

It is not a de Polignac number, because 21539342154239 - 2⁸ = 21539342153983 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21539342154259) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 456918647 + ... + 456965784.

It is an arithmetic number, because the mean of its divisors is an integer number (1154692979832).

Almost surely, 2^{21539342154239} is an apocalyptic number.

21539342154239 is a deficient number, since it is larger than the sum of its proper divisors (6173289361729).

21539342154239 is a wasteful number, since it uses less digits than its factorization.

21539342154239 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 913884495 (or 913884488 counting only the distinct ones).

The product of its digits is 6998400, while the sum is 53.

The spelling of 21539342154239 in words is "twenty-one trillion, five hundred thirty-nine billion, three hundred forty-two million, one hundred fifty-four thousand, two hundred thirty-nine".