9978749 has 6 divisors (see below), whose sum is σ = 10968510. Its totient is φ = 9071480.

The previous prime is 9978739. The next prime is 9978767. The reversal of 9978749 is 9478799.

9978749 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 9966649 + 12100 = 3157^2 + 110^2 .

It is not a de Polignac number, because 9978749 - 2⁴ = 9978733 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 9978749.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9978719) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 41114 + ... + 41355.

It is an arithmetic number, because the mean of its divisors is an integer number (1828085).

Almost surely, 2^9978749 is an apocalyptic number.

It is an amenable number.

9978749 is a deficient number, since it is larger than the sum of its proper divisors (989761).

9978749 is a wasteful number, since it uses less digits than its factorization.

9978749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82491 (or 82480 counting only the distinct ones).

The product of its digits is 1143072, while the sum is 53.

The square root of 9978749 is about 3158.9157950158. The cubic root of 9978749 is about 215.2907477974.

The spelling of 9978749 in words is "nine million, nine hundred seventy-eight thousand, seven hundred forty-nine".