15998481 has 6 divisors (see below), whose sum is σ = 23108930. Its totient is φ = 10665648.

The previous prime is 15998473. The next prime is 15998491. The reversal of 15998481 is 18489951.

It can be written as a sum of positive squares in only one way, i.e., 9828225 + 6170256 = 3135^2 + 2484^2 .

It is not a de Polignac number, because 15998481 - 2³ = 15998473 is a prime.

It is a super-2 number, since 2×15998481² = 511902788614722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15998491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 888796 + ... + 888813.

Almost surely, 2^15998481 is an apocalyptic number.

It is an amenable number.

15998481 is a deficient number, since it is larger than the sum of its proper divisors (7110449).

15998481 is a wasteful number, since it uses less digits than its factorization.

15998481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1777615 (or 1777612 counting only the distinct ones).

The product of its digits is 103680, while the sum is 45.

The square root of 15998481 is about 3999.8101204932. The cubic root of 15998481 is about 251.9762354763.

The spelling of 15998481 in words is "fifteen million, nine hundred ninety-eight thousand, four hundred eighty-one".