1389631 has 8 divisors (see below), whose sum is σ = 1506384. Its totient is φ = 1276800.

The previous prime is 1389629. The next prime is 1389643. The reversal of 1389631 is 1369831.

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

It is a cyclic number.

It is not a de Polignac number, because 1389631 - 2¹ = 1389629 is a prime.

It is a super-2 number, since 2×1389631² = 3862148632322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1389593 and 1389602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1389431) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 220 + ... + 1681.

It is an arithmetic number, because the mean of its divisors is an integer number (188298).

2^1389631 is an apocalyptic number.

1389631 is a deficient number, since it is larger than the sum of its proper divisors (116753).

1389631 is a wasteful number, since it uses less digits than its factorization.

1389631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1961.

The product of its digits is 3888, while the sum is 31.

The square root of 1389631 is about 1178.8261110104. The cubic root of 1389631 is about 111.5920265540.

The spelling of 1389631 in words is "one million, three hundred eighty-nine thousand, six hundred thirty-one".