16721226225 has 48 divisors (see below), whose sum is σ = 33510027840. Its totient is φ = 8107257600.

The previous prime is 16721226211. The next prime is 16721226229. The reversal of 16721226225 is 52262212761.

16721226225 is a `hidden beast` number, since 1 + 6 + 7 + 2 + 1 + 22 + 622 + 5 = 666.

It is not a de Polignac number, because 16721226225 - 2⁹ = 16721225713 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 16721226225.

It is not an unprimeable number, because it can be changed into a prime (16721226229) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 1118584 + ... + 1133433.

It is an arithmetic number, because the mean of its divisors is an integer number (698125580).

Almost surely, 2^16721226225 is an apocalyptic number.

16721226225 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

16721226225 is an abundant number, since it is smaller than the sum of its proper divisors (16788801615).

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

16721226225 is a wasteful number, since it uses less digits than its factorization.

16721226225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2252047 (or 2252036 counting only the distinct ones).

The product of its digits is 40320, while the sum is 36.

Adding to 16721226225 its reverse (52262212761), we get a palindrome (68983438986).

The spelling of 16721226225 in words is "sixteen billion, seven hundred twenty-one million, two hundred twenty-six thousand, two hundred twenty-five".