7881397 has 4 divisors (see below), whose sum is σ = 8015040. Its totient is φ = 7747756.

The previous prime is 7881373. The next prime is 7881487. The reversal of 7881397 is 7931887.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 7931887 = 223 ⋅35569.

It is a cyclic number.

It is not a de Polignac number, because 7881397 - 2¹⁵ = 7848629 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7881317) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66733 + ... + 66850.

It is an arithmetic number, because the mean of its divisors is an integer number (2003760).

Almost surely, 2^7881397 is an apocalyptic number.

It is an amenable number.

7881397 is a deficient number, since it is larger than the sum of its proper divisors (133643).

7881397 is a wasteful number, since it uses less digits than its factorization.

7881397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133642.

The product of its digits is 84672, while the sum is 43.

The square root of 7881397 is about 2807.3825888183. The cubic root of 7881397 is about 199.0067167754.

The spelling of 7881397 in words is "seven million, eight hundred eighty-one thousand, three hundred ninety-seven".