16221322425 has 96 divisors (see below), whose sum is σ = 33651846144. Its totient is φ = 6698016000.

The previous prime is 16221322421. The next prime is 16221322433. The reversal of 16221322425 is 52422312261.

It is not a de Polignac number, because 16221322425 - 2² = 16221322421 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 16221322392 and 16221322401.

It is not an unprimeable number, because it can be changed into a prime (16221322421) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 897730 + ... + 915620.

It is an arithmetic number, because the mean of its divisors is an integer number (350540064).

Almost surely, 2^16221322425 is an apocalyptic number.

16221322425 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

16221322425 is an abundant number, since it is smaller than the sum of its proper divisors (17430523719).

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

16221322425 is a wasteful number, since it uses less digits than its factorization.

16221322425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18079 (or 18074 counting only the distinct ones).

The product of its digits is 11520, while the sum is 30.

Adding to 16221322425 its reverse (52422312261), we get a palindrome (68643634686).

The spelling of 16221322425 in words is "sixteen billion, two hundred twenty-one million, three hundred twenty-two thousand, four hundred twenty-five".