21530545152125 has 32 divisors (see below), whose sum is σ = 27592855804800. Its totient is φ = 16763995248000.

The previous prime is 21530545152089. The next prime is 21530545152143. The reversal of 21530545152125 is 52125154503512.

It is not a de Polignac number, because 21530545152125 - 2¹⁴ = 21530545135741 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5617175 + ... + 8637924.

It is an arithmetic number, because the mean of its divisors is an integer number (862276743900).

Almost surely, 2^{21530545152125} is an apocalyptic number.

21530545152125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21530545152125 is a deficient number, since it is larger than the sum of its proper divisors (6062310652675).

21530545152125 is a wasteful number, since it uses less digits than its factorization.

21530545152125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14255438 (or 14255428 counting only the distinct ones).

The product of its (nonzero) digits is 300000, while the sum is 41.

Adding to 21530545152125 its reverse (52125154503512), we get a palindrome (73655699655637).

The spelling of 21530545152125 in words is "twenty-one trillion, five hundred thirty billion, five hundred forty-five million, one hundred fifty-two thousand, one hundred twenty-five".