7689891989 has 8 divisors (see below), whose sum is σ = 8366799000. Its totient is φ = 7025181696.

The previous prime is 7689891977. The next prime is 7689891997. The reversal of 7689891989 is 9891989867.

It can be written as a sum of positive squares in 4 ways, for example, as 1966212964 + 5723679025 = 44342^2 + 75655^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 7689891989 - 2¹² = 7689887893 is a prime.

It is a super-2 number, since 2×7689891989² (a number of 21 digits) 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 (7689891689) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3047864 + ... + 3050385.

It is an arithmetic number, because the mean of its divisors is an integer number (1045849875).

Almost surely, 2^7689891989 is an apocalyptic number.

It is an amenable number.

7689891989 is a deficient number, since it is larger than the sum of its proper divisors (676907011).

7689891989 is a wasteful number, since it uses less digits than its factorization.

7689891989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6098359.

The product of its digits is 141087744, while the sum is 74.

The square root of 7689891989 is about 87692.0292215889. The cubic root of 7689891989 is about 1973.8163704413.

The spelling of 7689891989 in words is "seven billion, six hundred eighty-nine million, eight hundred ninety-one thousand, nine hundred eighty-nine".