21011520434 has 8 divisors (see below), whose sum is σ = 31548152748. Its totient is φ = 10495469520.

The previous prime is 21011520433. The next prime is 21011520437. The reversal of 21011520434 is 43402511012.

It can be written as a sum of positive squares in 2 ways, for example, as 21011372209 + 148225 = 144953^2 + 385^2 .

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

It is not an unprimeable number, because it can be changed into a prime (21011520433) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5142797 + ... + 5146880.

Almost surely, 2^21011520434 is an apocalyptic number.

21011520434 is a deficient number, since it is larger than the sum of its proper divisors (10536632314).

21011520434 is a wasteful number, since it uses less digits than its factorization.

21011520434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10290700.

The product of its (nonzero) digits is 960, while the sum is 23.

The spelling of 21011520434 in words is "twenty-one billion, eleven million, five hundred twenty thousand, four hundred thirty-four".