16221142481 has 8 divisors (see below), whose sum is σ = 16397954664. Its totient is φ = 16044526080.

The previous prime is 16221142447. The next prime is 16221142493. The reversal of 16221142481 is 18424112261.

It can be written as a sum of positive squares in 4 ways, for example, as 88078225 + 16133064256 = 9385^2 + 127016^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 16221142481 - 2¹⁰ = 16221141457 is a prime.

It is a super-2 number, since 2×16221142481² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16221142381) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 120851 + ... + 216903.

It is an arithmetic number, because the mean of its divisors is an integer number (2049744333).

Almost surely, 2^16221142481 is an apocalyptic number.

It is an amenable number.

16221142481 is a deficient number, since it is larger than the sum of its proper divisors (176812183).

16221142481 is an equidigital number, since it uses as much as digits as its factorization.

16221142481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97891.

The product of its digits is 6144, while the sum is 32.

The spelling of 16221142481 in words is "sixteen billion, two hundred twenty-one million, one hundred forty-two thousand, four hundred eighty-one".