21531351030225 has 24 divisors (see below), whose sum is σ = 35598724779840. Its totient is φ = 11483314825920.

The previous prime is 21531351030209. The next prime is 21531351030239. The reversal of 21531351030225 is 52203015313512.

It is not a de Polignac number, because 21531351030225 - 2⁴ = 21531351030209 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12359491 + ... + 13993559.

It is an arithmetic number, because the mean of its divisors is an integer number (1483280199160).

Almost surely, 2^{21531351030225} is an apocalyptic number.

21531351030225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21531351030225 is a deficient number, since it is larger than the sum of its proper divisors (14067373749615).

21531351030225 is a wasteful number, since it uses less digits than its factorization.

21531351030225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1809769 (or 1809764 counting only the distinct ones).

The product of its (nonzero) digits is 27000, while the sum is 33.

Adding to 21531351030225 its reverse (52203015313512), we get a palindrome (73734366343737).

The spelling of 21531351030225 in words is "twenty-one trillion, five hundred thirty-one billion, three hundred fifty-one million, thirty thousand, two hundred twenty-five".