64978945 has 16 divisors (see below), whose sum is σ = 81704448. Its totient is φ = 49547520.

The previous prime is 64978943. The next prime is 64978951. The reversal of 64978945 is 54987946.

It is a happy number.

It is not a de Polignac number, because 64978945 - 2¹ = 64978943 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 64978892 and 64978901.

It is not an unprimeable number, because it can be changed into a prime (64978943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7257 + ... + 13513.

It is an arithmetic number, because the mean of its divisors is an integer number (5106528).

It is a Proth number, since it is equal to 1983 ⋅ 2¹⁵ + 1 and 1983 < 2¹⁵.

Almost surely, 2^64978945 is an apocalyptic number.

It is an amenable number.

64978945 is a deficient number, since it is larger than the sum of its proper divisors (16725503).

64978945 is a wasteful number, since it uses less digits than its factorization.

64978945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6360.

The product of its digits is 2177280, while the sum is 52.

The square root of 64978945 is about 8060.9518668703. The cubic root of 64978945 is about 402.0291576419.

Subtracting from 64978945 its reverse (54987946), we obtain a palindrome (9990999).

The spelling of 64978945 in words is "sixty-four million, nine hundred seventy-eight thousand, nine hundred forty-five".