28477481 has 4 divisors (see below), whose sum is σ = 29139792. Its totient is φ = 27815172.

The previous prime is 28477459. The next prime is 28477487. The reversal of 28477481 is 18477482.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18477482 = 2 ⋅9238741.

It is a cyclic number.

It is not a de Polignac number, because 28477481 - 2⁶ = 28477417 is a prime.

It is a super-2 number, since 2×28477481² = 1621933848210722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28477487) 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, 331091 + ... + 331176.

It is an arithmetic number, because the mean of its divisors is an integer number (7284948).

Almost surely, 2^28477481 is an apocalyptic number.

It is an amenable number.

28477481 is a deficient number, since it is larger than the sum of its proper divisors (662311).

28477481 is an equidigital number, since it uses as much as digits as its factorization.

28477481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 662310.

The product of its digits is 100352, while the sum is 41.

The square root of 28477481 is about 5336.4296116411. The cubic root of 28477481 is about 305.3752650482.

Subtracting from 28477481 its reverse (18477482), we obtain a palindrome (9999999).

The spelling of 28477481 in words is "twenty-eight million, four hundred seventy-seven thousand, four hundred eighty-one".