15138481 has 4 divisors (see below), whose sum is σ = 15146352. Its totient is φ = 15130612.

The previous prime is 15138463. The next prime is 15138523. The reversal of 15138481 is 18483151.

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 a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 15138481 - 2⁷ = 15138353 is a prime.

It is a super-2 number, since 2×15138481² = 458347213974722, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15138581) 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, 1086 + ... + 5608.

It is an arithmetic number, because the mean of its divisors is an integer number (3786588).

Almost surely, 2^15138481 is an apocalyptic number.

It is an amenable number.

15138481 is a deficient number, since it is larger than the sum of its proper divisors (7871).

15138481 is an equidigital number, since it uses as much as digits as its factorization.

15138481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7870.

The product of its digits is 3840, while the sum is 31.

The square root of 15138481 is about 3890.8200935021. The cubic root of 15138481 is about 247.3778249497.

The spelling of 15138481 in words is "fifteen million, one hundred thirty-eight thousand, four hundred eighty-one".