64632978 has 20 divisors (see below), whose sum is σ = 144826110. Its totient is φ = 21544272.

The previous prime is 64632961. The next prime is 64632979. The reversal of 64632978 is 87923646.

64632978 is a `hidden beast` number, since 6 + 4 + 632 + 9 + 7 + 8 = 666.

64632978 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 52751169 + 11881809 = 7263^2 + 3447^2 .

It is not an unprimeable number, because it can be changed into a prime (64632979) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 199323 + ... + 199646.

Almost surely, 2^64632978 is an apocalyptic number.

64632978 is an abundant number, since it is smaller than the sum of its proper divisors (80193132).

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

64632978 is a wasteful number, since it uses less digits than its factorization.

64632978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 398983 (or 398974 counting only the distinct ones).

The product of its digits is 435456, while the sum is 45.

The square root of 64632978 is about 8039.4637880894. The cubic root of 64632978 is about 401.3143804461.

The spelling of 64632978 in words is "sixty-four million, six hundred thirty-two thousand, nine hundred seventy-eight".