21520500531406 has 4 divisors (see below), whose sum is σ = 32280750797112. Its totient is φ = 10760250265702.

The previous prime is 21520500531359. The next prime is 21520500531421. The reversal of 21520500531406 is 60413500502512.

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 (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5380125132850 + ... + 5380125132853.

It is an arithmetic number, because the mean of its divisors is an integer number (8070187699278).

Almost surely, 2^{21520500531406} is an apocalyptic number.

21520500531406 is a deficient number, since it is larger than the sum of its proper divisors (10760250265706).

21520500531406 is a wasteful number, since it uses less digits than its factorization.

21520500531406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10760250265705.

The product of its (nonzero) digits is 36000, while the sum is 34.

The spelling of 21520500531406 in words is "twenty-one trillion, five hundred twenty billion, five hundred million, five hundred thirty-one thousand, four hundred six".