1389718491 has 16 divisors (see below), whose sum is σ = 2118302208. Its totient is φ = 793886400.

The previous prime is 1389718487. The next prime is 1389718511. The reversal of 1389718491 is 1948179831.

It is a happy number.

It is not a de Polignac number, because 1389718491 - 2² = 1389718487 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1389718471) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 81031 + ... + 96671.

It is an arithmetic number, because the mean of its divisors is an integer number (132393888).

Almost surely, 2^1389718491 is an apocalyptic number.

1389718491 is a deficient number, since it is larger than the sum of its proper divisors (728583717).

1389718491 is a wasteful number, since it uses less digits than its factorization.

1389718491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19882.

The product of its digits is 435456, while the sum is 51.

The square root of 1389718491 is about 37278.9282437143. The cubic root of 1389718491 is about 1115.9436844503.

The spelling of 1389718491 in words is "one billion, three hundred eighty-nine million, seven hundred eighteen thousand, four hundred ninety-one".