1391597138 has 8 divisors (see below), whose sum is σ = 2087608140. Its totient is φ = 695727760.

The previous prime is 1391597131. The next prime is 1391597153. The reversal of 1391597138 is 8317951931.

It can be written as a sum of positive squares in 2 ways, for example, as 1172172169 + 219424969 = 34237^2 + 14813^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 1391597092 and 1391597101.

It is not an unprimeable number, because it can be changed into a prime (1391597131) 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, 5933 + ... + 53088.

Almost surely, 2^1391597138 is an apocalyptic number.

1391597138 is a deficient number, since it is larger than the sum of its proper divisors (696011002).

1391597138 is a wasteful number, since it uses less digits than its factorization.

1391597138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70812.

The product of its digits is 204120, while the sum is 47.

The square root of 1391597138 is about 37304.1169041702. The cubic root of 1391597138 is about 1116.4463090940.

The spelling of 1391597138 in words is "one billion, three hundred ninety-one million, five hundred ninety-seven thousand, one hundred thirty-eight".