15897481 has 4 divisors (see below), whose sum is σ = 16445700. Its totient is φ = 15349264.

The previous prime is 15897473. The next prime is 15897493. The reversal of 15897481 is 18479851.

It is a happy number.

15897481 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18479851 = 13 ⋅1421527.

It can be written as a sum of positive squares in 2 ways, for example, as 2611456 + 13286025 = 1616^2 + 3645^2 .

It is a cyclic number.

It is not a de Polignac number, because 15897481 - 2³ = 15897473 is a prime.

It is a super-2 number, since 2×15897481² = 505459804290722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15894481) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 274066 + ... + 274123.

It is an arithmetic number, because the mean of its divisors is an integer number (4111425).

Almost surely, 2^15897481 is an apocalyptic number.

It is an amenable number.

15897481 is a deficient number, since it is larger than the sum of its proper divisors (548219).

15897481 is an equidigital number, since it uses as much as digits as its factorization.

15897481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 548218.

The product of its digits is 80640, while the sum is 43.

The square root of 15897481 is about 3987.1645313430. The cubic root of 15897481 is about 251.4448653690. Note that the first 3 decimals are identical.

The spelling of 15897481 in words is "fifteen million, eight hundred ninety-seven thousand, four hundred eighty-one".