64943978 has 16 divisors (see below), whose sum is σ = 112523904. Its totient is φ = 27783360.

The previous prime is 64943969. The next prime is 64943981. The reversal of 64943978 is 87934946.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 86450 + ... + 87197.

It is an arithmetic number, because the mean of its divisors is an integer number (7032744).

Almost surely, 2^64943978 is an apocalyptic number.

64943978 is a deficient number, since it is larger than the sum of its proper divisors (47579926).

64943978 is a wasteful number, since it uses less digits than its factorization.

64943978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173677.

The product of its digits is 1306368, while the sum is 50.

The square root of 64943978 is about 8058.7826624125. The cubic root of 64943978 is about 401.9570302990.

The spelling of 64943978 in words is "sixty-four million, nine hundred forty-three thousand, nine hundred seventy-eight".