978977664 has 480 divisors, whose sum is σ = 3545609760. Its totient is φ = 267079680.

The previous prime is 978977663. The next prime is 978977719. The reversal of 978977664 is 466779879.

It is a super-2 number, since 2×978977664² = 1916794533221793792, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a nude number because it is divisible by every one of its digits.

Its product of digits (32006016) is a multiple of the sum of its prime factors (128).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (978977663) 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 59 ways as a sum of consecutive naturals, for example, 20829289 + ... + 20829335.

It is an arithmetic number, because the mean of its divisors is an integer number (7386687).

Almost surely, 2^978977664 is an apocalyptic number.

978977664 is a gapful number since it is divisible by the number (94) 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 978977664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1772804880).

978977664 is an abundant number, since it is smaller than the sum of its proper divisors (2566632096).

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

978977664 is a wasteful number, since it uses less digits than its factorization.

978977664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128 (or 100 counting only the distinct ones).

The product of its digits is 32006016, while the sum is 63.

The square root of 978977664 is about 31288.6187614602. The cubic root of 978977664 is about 992.9428687204.

The spelling of 978977664 in words is "nine hundred seventy-eight million, nine hundred seventy-seven thousand, six hundred sixty-four".