7981387 has 4 divisors (see below), whose sum is σ = 8401480. Its totient is φ = 7561296.

The previous prime is 7981339. The next prime is 7981397. The reversal of 7981387 is 7831897.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7981387 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7981327) 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, 210018 + ... + 210055.

It is an arithmetic number, because the mean of its divisors is an integer number (2100370).

Almost surely, 2^7981387 is an apocalyptic number.

7981387 is a deficient number, since it is larger than the sum of its proper divisors (420093).

7981387 is a wasteful number, since it uses less digits than its factorization.

7981387 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 420092.

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

The square root of 7981387 is about 2825.1348640375. The cubic root of 7981387 is about 199.8447712180.

The spelling of 7981387 in words is "seven million, nine hundred eighty-one thousand, three hundred eighty-seven".