1397638 has 32 divisors (see below), whose sum is σ = 2511648. Its totient is φ = 576000.

The previous prime is 1397633. The next prime is 1397657. The reversal of 1397638 is 8367931.

It is a Harshad number since it is a multiple of its sum of digits (37).

Its product of digits (27216) is a multiple of the sum of its prime divisors (168).

It is a junction number, because it is equal to n+sod(n) for n = 1397597 and 1397606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1397633) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13788 + ... + 13888.

It is an arithmetic number, because the mean of its divisors is an integer number (78489).

2^1397638 is an apocalyptic number.

1397638 is the 748-th heptagonal number.

1397638 is a deficient number, since it is larger than the sum of its proper divisors (1114010).

1397638 is a wasteful number, since it uses less digits than its factorization.

1397638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168.

The product of its digits is 27216, while the sum is 37.

The square root of 1397638 is about 1182.2174080938. The cubic root of 1397638 is about 111.8059458586.

It can be divided in two parts, 139 and 7638, that added together give a palindrome (7777).

The spelling of 1397638 in words is "one million, three hundred ninety-seven thousand, six hundred thirty-eight".