21225108671 has 24 divisors (see below), whose sum is σ = 23879260080. Its totient is φ = 18834606336.

The previous prime is 21225108659. The next prime is 21225108727. The reversal of 21225108671 is 17680152212.

It is not a de Polignac number, because 21225108671 - 2¹⁰ = 21225107647 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21225108631) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1132640 + ... + 1151226.

It is an arithmetic number, because the mean of its divisors is an integer number (994969170).

Almost surely, 2^21225108671 is an apocalyptic number.

21225108671 is a deficient number, since it is larger than the sum of its proper divisors (2654151409).

21225108671 is a wasteful number, since it uses less digits than its factorization.

21225108671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18875 (or 18862 counting only the distinct ones).

The product of its (nonzero) digits is 13440, while the sum is 35.

The spelling of 21225108671 in words is "twenty-one billion, two hundred twenty-five million, one hundred eight thousand, six hundred seventy-one".