21512534102220 has 48 divisors (see below), whose sum is σ = 68840109128448. Its totient is φ = 4917150651840.

The previous prime is 21512534102159. The next prime is 21512534102327. The reversal of 21512534102220 is 2220143521512.

It is a super-2 number, since 2×21512534102220² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

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 in 15 ways as a sum of consecutive naturals, for example, 25610159226 + ... + 25610160065.

It is an arithmetic number, because the mean of its divisors is an integer number (1434168940176).

Almost surely, 2^{21512534102220} is an apocalyptic number.

21512534102220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21512534102220 is an abundant number, since it is smaller than the sum of its proper divisors (47327575026228).

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

21512534102220 is a wasteful number, since it uses less digits than its factorization.

21512534102220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51220319310 (or 51220319308 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 30.

Adding to 21512534102220 its reverse (2220143521512), we get a palindrome (23732677623732).

The spelling of 21512534102220 in words is "twenty-one trillion, five hundred twelve billion, five hundred thirty-four million, one hundred two thousand, two hundred twenty".