21506206002050 has 48 divisors (see below), whose sum is σ = 49872053823552. Its totient is φ = 6703233038400.

The previous prime is 21506206002031. The next prime is 21506206002091. The reversal of 21506206002050 is 5020060260512.

It is a super-2 number, since 2×21506206002050² (a number of 27 digits) contains 22 as substring.

It is a Curzon 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 23 ways as a sum of consecutive naturals, for example, 2793009917 + ... + 2793017616.

It is an arithmetic number, because the mean of its divisors is an integer number (1039001121324).

Almost surely, 2^{21506206002050} is an apocalyptic number.

21506206002050 is an abundant number, since it is smaller than the sum of its proper divisors (28365847821502).

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

21506206002050 is a wasteful number, since it uses less digits than its factorization.

21506206002050 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5586027563 (or 5586027558 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 29.

Adding to 21506206002050 its reverse (5020060260512), we get a palindrome (26526266262562).

The spelling of 21506206002050 in words is "twenty-one trillion, five hundred six billion, two hundred six million, two thousand, fifty".