7971138 has 48 divisors (see below), whose sum is σ = 20232576. Its totient is φ = 2220480.

The previous prime is 7971137. The next prime is 7971149. The reversal of 7971138 is 8311797.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7971137) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4395 + ... + 5937.

It is an arithmetic number, because the mean of its divisors is an integer number (421512).

Almost surely, 2^7971138 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 7971138, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10116288).

7971138 is an abundant number, since it is smaller than the sum of its proper divisors (12261438).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

7971138 is a wasteful number, since it uses less digits than its factorization.

7971138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1599 (or 1596 counting only the distinct ones).

The product of its digits is 10584, while the sum is 36.

The square root of 7971138 is about 2823.3203856452. The cubic root of 7971138 is about 199.7591935109.

It can be divided in two parts, 79 and 71138, that added together give a palindrome (71217).

The spelling of 7971138 in words is "seven million, nine hundred seventy-one thousand, one hundred thirty-eight".