1994478464 has 64 divisors (see below), whose sum is σ = 4426963200. Its totient is φ = 887262720.

The previous prime is 1994478449. The next prime is 1994478467. The reversal of 1994478464 is 4648744991.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1994478467) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 51107 + ... + 81245.

It is an arithmetic number, because the mean of its divisors is an integer number (69171300).

Almost surely, 2^1994478464 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1994478464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2213481600).

1994478464 is an abundant number, since it is smaller than the sum of its proper divisors (2432484736).

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

1994478464 is a wasteful number, since it uses less digits than its factorization.

1994478464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30211 (or 30199 counting only the distinct ones).

The product of its digits is 6967296, while the sum is 56.

The square root of 1994478464 is about 44659.5842345179. The cubic root of 1994478464 is about 1258.7605313589.

The spelling of 1994478464 in words is "one billion, nine hundred ninety-four million, four hundred seventy-eight thousand, four hundred sixty-four".