21152515402342 has 4 divisors (see below), whose sum is σ = 31728773103516. Its totient is φ = 10576257701170.

The previous prime is 21152515402253. The next prime is 21152515402387. The reversal of 21152515402342 is 24320451525112.

It is a semiprime because it is the product of two primes.

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 as a sum of consecutive naturals, namely, 5288128850584 + ... + 5288128850587.

It is an arithmetic number, because the mean of its divisors is an integer number (7932193275879).

Almost surely, 2^{21152515402342} is an apocalyptic number.

21152515402342 is a deficient number, since it is larger than the sum of its proper divisors (10576257701174).

21152515402342 is a wasteful number, since it uses less digits than its factorization.

21152515402342 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10576257701173.

The product of its (nonzero) digits is 96000, while the sum is 37.

Adding to 21152515402342 its reverse (24320451525112), we get a palindrome (45472966927454).

The spelling of 21152515402342 in words is "twenty-one trillion, one hundred fifty-two billion, five hundred fifteen million, four hundred two thousand, three hundred forty-two".