7947987 has 4 divisors (see below), whose sum is σ = 10597320. Its totient is φ = 5298656.

The previous prime is 7947983. The next prime is 7948019. The reversal of 7947987 is 7897497.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7897497 = 3 ⋅2632499.

It is a cyclic number.

It is not a de Polignac number, because 7947987 - 2² = 7947983 is a prime.

It is not an unprimeable number, because it can be changed into a prime (7947983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1324662 + ... + 1324667.

It is an arithmetic number, because the mean of its divisors is an integer number (2649330).

Almost surely, 2^7947987 is an apocalyptic number.

7947987 is a deficient number, since it is larger than the sum of its proper divisors (2649333).

7947987 is a wasteful number, since it uses less digits than its factorization.

7947987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2649332.

The product of its digits is 889056, while the sum is 51.

The square root of 7947987 is about 2819.2174446112. The cubic root of 7947987 is about 199.5656155672.

It can be divided in two parts, 79 and 47987, that multiplied together give a palindrome (3790973).

The spelling of 7947987 in words is "seven million, nine hundred forty-seven thousand, nine hundred eighty-seven".