9776721 has 8 divisors (see below), whose sum is σ = 13050784. Its totient is φ = 6510240.

The previous prime is 9776693. The next prime is 9776729. The reversal of 9776721 is 1276779.

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

It is not a de Polignac number, because 9776721 - 2⁷ = 9776593 is a prime.

It is a Duffinian number.

9776721 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 9776721.

It is not an unprimeable number, because it can be changed into a prime (9776729) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2730 + ... + 5196.

It is an arithmetic number, because the mean of its divisors is an integer number (1631348).

Almost surely, 2^9776721 is an apocalyptic number.

It is an amenable number.

9776721 is a deficient number, since it is larger than the sum of its proper divisors (3274063).

9776721 is a wasteful number, since it uses less digits than its factorization.

9776721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3791.

The product of its digits is 37044, while the sum is 39.

The square root of 9776721 is about 3126.7748559818. The cubic root of 9776721 is about 213.8279179699.

The spelling of 9776721 in words is "nine million, seven hundred seventy-six thousand, seven hundred twenty-one".