21225112051251 has 16 divisors (see below), whose sum is σ = 28320187705344. Its totient is φ = 14140058825664.

The previous prime is 21225112051237. The next prime is 21225112051259. The reversal of 21225112051251 is 15215021152212.

It is a happy number.

It is not a de Polignac number, because 21225112051251 - 2¹⁵ = 21225112018483 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21225112051259) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25700095 + ... + 26513111.

It is an arithmetic number, because the mean of its divisors is an integer number (1770011731584).

Almost surely, 2^{21225112051251} is an apocalyptic number.

21225112051251 is a deficient number, since it is larger than the sum of its proper divisors (7095075654093).

21225112051251 is a wasteful number, since it uses less digits than its factorization.

21225112051251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 819170.

The product of its (nonzero) digits is 4000, while the sum is 30.

The spelling of 21225112051251 in words is "twenty-one trillion, two hundred twenty-five billion, one hundred twelve million, fifty-one thousand, two hundred fifty-one".