8644919478 has 64 divisors (see below), whose sum is σ = 19670515200. Its totient is φ = 2510887680.

The previous prime is 8644919473. The next prime is 8644919489. The reversal of 8644919478 is 8749194468.

It is a super-2 number, since 2×8644919478² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8644919473) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 406063 + ... + 426821.

It is an arithmetic number, because the mean of its divisors is an integer number (307351800).

Almost surely, 2^8644919478 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 8644919478, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (9835257600).

8644919478 is an abundant number, since it is smaller than the sum of its proper divisors (11025595722).

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

8644919478 is a wasteful number, since it uses less digits than its factorization.

8644919478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21077.

The product of its digits is 13934592, while the sum is 60.

The square root of 8644919478 is about 92978.0591214938. The cubic root of 8644919478 is about 2052.3605153160.

The spelling of 8644919478 in words is "eight billion, six hundred forty-four million, nine hundred nineteen thousand, four hundred seventy-eight".