1391899049 has 4 divisors (see below), whose sum is σ = 1405412736. Its totient is φ = 1378385364.

The previous prime is 1391899013. The next prime is 1391899057. The reversal of 1391899049 is 9409981931.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1391899049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1391899009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6756689 + ... + 6756894.

It is an arithmetic number, because the mean of its divisors is an integer number (351353184).

Almost surely, 2^1391899049 is an apocalyptic number.

It is an amenable number.

1391899049 is a deficient number, since it is larger than the sum of its proper divisors (13513687).

1391899049 is a wasteful number, since it uses less digits than its factorization.

1391899049 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13513686.

The product of its (nonzero) digits is 629856, while the sum is 53.

The square root of 1391899049 is about 37308.1633024195. The cubic root of 1391899049 is about 1116.5270420014.

The spelling of 1391899049 in words is "one billion, three hundred ninety-one million, eight hundred ninety-nine thousand, forty-nine".