21151215534 has 8 divisors (see below), whose sum is σ = 42302431080. Its totient is φ = 7050405176.

The previous prime is 21151215529. The next prime is 21151215577. The reversal of 21151215534 is 43551215112.

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

21151215534 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1762601289 + ... + 1762601300.

It is an arithmetic number, because the mean of its divisors is an integer number (5287803885).

Almost surely, 2^21151215534 is an apocalyptic number.

21151215534 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21151215534 is a wasteful number, since it uses less digits than its factorization.

21151215534 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3525202594.

The product of its digits is 6000, while the sum is 30.

The spelling of 21151215534 in words is "twenty-one billion, one hundred fifty-one million, two hundred fifteen thousand, five hundred thirty-four".