21500520051010 has 96 divisors (see below), whose sum is σ = 52889990755392. Its totient is φ = 6185963790720.

The previous prime is 21500520050951. The next prime is 21500520051019. The reversal of 21500520051010 is 1015002500512.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is not an unprimeable number, because it can be changed into a prime (21500520051019) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 153351652 + ... + 153491791.

It is an arithmetic number, because the mean of its divisors is an integer number (550937403702).

Almost surely, 2^{21500520051010} is an apocalyptic number.

21500520051010 is an abundant number, since it is smaller than the sum of its proper divisors (31389470704382).

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

21500520051010 is a wasteful number, since it uses less digits than its factorization.

21500520051010 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 306843488 (or 306843481 counting only the distinct ones).

The product of its (nonzero) digits is 500, while the sum is 22.

Adding to 21500520051010 its reverse (1015002500512), we get a palindrome (22515522551522).

The spelling of 21500520051010 in words is "twenty-one trillion, five hundred billion, five hundred twenty million, fifty-one thousand, ten".