9777891 has 8 divisors (see below), whose sum is σ = 13171984. Its totient is φ = 6451200.

The previous prime is 9777883. The next prime is 9777919. The reversal of 9777891 is 1987779.

9777891 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 9777891 - 2³ = 9777883 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 9777891.

It is not an unprimeable number, because it can be changed into a prime (9777851) 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, 16510 + ... + 17091.

It is an arithmetic number, because the mean of its divisors is an integer number (1646498).

Almost surely, 2^9777891 is an apocalyptic number.

9777891 is a deficient number, since it is larger than the sum of its proper divisors (3394093).

9777891 is a wasteful number, since it uses less digits than its factorization.

9777891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33701.

The product of its digits is 222264, while the sum is 48.

The square root of 9777891 is about 3126.9619441240. The cubic root of 9777891 is about 213.8364473696.

The spelling of 9777891 in words is "nine million, seven hundred seventy-seven thousand, eight hundred ninety-one".