9978182640 has 480 divisors, whose sum is σ = 37266989760. Its totient is φ = 2472394752.

The previous prime is 9978182603. The next prime is 9978182647. The reversal of 9978182640 is 462818799.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9978182647) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 36022182 + ... + 36022458.

It is an arithmetic number, because the mean of its divisors is an integer number (77639562).

Almost surely, 2^9978182640 is an apocalyptic number.

9978182640 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 9978182640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18633494880).

9978182640 is an abundant number, since it is smaller than the sum of its proper divisors (27288807120).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

9978182640 is a wasteful number, since it uses less digits than its factorization.

9978182640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 431 (or 413 counting only the distinct ones).

The product of its (nonzero) digits is 1741824, while the sum is 54.

The square root of 9978182640 is about 99890.8536353554. The cubic root of 9978182640 is about 2152.8667466246.

The spelling of 9978182640 in words is "nine billion, nine hundred seventy-eight million, one hundred eighty-two thousand, six hundred forty".