1378658689 has 4 divisors (see below), whose sum is σ = 1379455956. Its totient is φ = 1377861424.

The previous prime is 1378658681. The next prime is 1378658711. The reversal of 1378658689 is 9868568731.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 942183025 + 436475664 = 30695^2 + 20892^2 .

It is a cyclic number.

It is not a de Polignac number, because 1378658689 - 2³ = 1378658681 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1378658681) 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, 396034 + ... + 399499.

It is an arithmetic number, because the mean of its divisors is an integer number (344863989).

Almost surely, 2^1378658689 is an apocalyptic number.

It is an amenable number.

1378658689 is a deficient number, since it is larger than the sum of its proper divisors (797267).

1378658689 is an equidigital number, since it uses as much as digits as its factorization.

1378658689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 797266.

The product of its digits is 17418240, while the sum is 61.

The square root of 1378658689 is about 37130.2934138690. The cubic root of 1378658689 is about 1112.9754568147.

The spelling of 1378658689 in words is "one billion, three hundred seventy-eight million, six hundred fifty-eight thousand, six hundred eighty-nine".