1978624064 has 42 divisors (see below), whose sum is σ = 4066502154. Its totient is φ = 955171840.

The previous prime is 1978624051. The next prime is 1978624079. The reversal of 1978624064 is 4604268791.

It can be written as a sum of positive squares in 3 ways, for example, as 6553600 + 1972070464 = 2560^2 + 44408^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 35444 + ... + 72204.

Almost surely, 2^1978624064 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 1978624064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2033251077).

1978624064 is an abundant number, since it is smaller than the sum of its proper divisors (2087878090).

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

1978624064 is an equidigital number, since it uses as much as digits as its factorization.

1978624064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36831 (or 36792 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 47.

The square root of 1978624064 is about 44481.7273045910. The cubic root of 1978624064 is about 1255.4162974006.

The spelling of 1978624064 in words is "one billion, nine hundred seventy-eight million, six hundred twenty-four thousand, sixty-four".