21131336734 has 8 divisors (see below), whose sum is σ = 31938967368. Its totient is φ = 10485014280.

The previous prime is 21131336729. The next prime is 21131336741. The reversal of 21131336734 is 43763313112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21131336734.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 40326717 + ... + 40327240.

It is an arithmetic number, because the mean of its divisors is an integer number (3992370921).

Almost surely, 2^21131336734 is an apocalyptic number.

21131336734 is a deficient number, since it is larger than the sum of its proper divisors (10807630634).

21131336734 is a wasteful number, since it uses less digits than its factorization.

21131336734 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80654090.

The product of its digits is 27216, while the sum is 34.

Adding to 21131336734 its reverse (43763313112), we get a palindrome (64894649846).

The spelling of 21131336734 in words is "twenty-one billion, one hundred thirty-one million, three hundred thirty-six thousand, seven hundred thirty-four".