7889981 has 4 divisors (see below), whose sum is σ = 8607264. Its totient is φ = 7172700.

The previous prime is 7889977. The next prime is 7890013. The reversal of 7889981 is 1899887.

It is a happy number.

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: 1899887 = 11 ⋅172717.

It is a cyclic number.

It is not a de Polignac number, because 7889981 - 2² = 7889977 is a prime.

It is a super-2 number, since 2×7889981² = 124503600360722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7889281) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 358625 + ... + 358646.

It is an arithmetic number, because the mean of its divisors is an integer number (2151816).

Almost surely, 2^7889981 is an apocalyptic number.

It is an amenable number.

7889981 is a deficient number, since it is larger than the sum of its proper divisors (717283).

7889981 is a wasteful number, since it uses less digits than its factorization.

7889981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 717282.

The product of its digits is 290304, while the sum is 50.

The square root of 7889981 is about 2808.9109989460. The cubic root of 7889981 is about 199.0789397516.

It can be divided in two parts, 7 and 889981, that added together give a palindrome (889988).

The spelling of 7889981 in words is "seven million, eight hundred eighty-nine thousand, nine hundred eighty-one".