1538375649 has 4 divisors (see below), whose sum is σ = 2051167536. Its totient is φ = 1025583764.

The previous prime is 1538375599. The next prime is 1538375711. The reversal of 1538375649 is 9465738351.

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: 9465738351 = 3 ⋅3155246117.

It is a cyclic number.

It is not a de Polignac number, because 1538375649 - 2⁸ = 1538375393 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1538375249) 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, 256395939 + ... + 256395944.

It is an arithmetic number, because the mean of its divisors is an integer number (512791884).

Almost surely, 2^1538375649 is an apocalyptic number.

It is an amenable number.

1538375649 is a deficient number, since it is larger than the sum of its proper divisors (512791887).

1538375649 is an equidigital number, since it uses as much as digits as its factorization.

1538375649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 512791886.

The product of its digits is 2721600, while the sum is 51.

The square root of 1538375649 is about 39222.1321322541. The cubic root of 1538375649 is about 1154.3941899007.

The spelling of 1538375649 in words is "one billion, five hundred thirty-eight million, three hundred seventy-five thousand, six hundred forty-nine".