64806820 has 24 divisors (see below), whose sum is σ = 146563704. Its totient is φ = 23928576.

The previous prime is 64806811. The next prime is 64806823. The reversal of 64806820 is 2860846.

It can be written as a sum of positive squares in 4 ways, for example, as 14197824 + 50608996 = 3768^2 + 7114^2 .

It is not an unprimeable number, because it can be changed into a prime (64806823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 124369 + ... + 124888.

It is an arithmetic number, because the mean of its divisors is an integer number (6106821).

Almost surely, 2^64806820 is an apocalyptic number.

It is an amenable number.

64806820 is an abundant number, since it is smaller than the sum of its proper divisors (81756884).

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

64806820 is a wasteful number, since it uses less digits than its factorization.

64806820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 249279 (or 249277 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 34.

The square root of 64806820 is about 8050.2683185096. The cubic root of 64806820 is about 401.6738607053.

The spelling of 64806820 in words is "sixty-four million, eight hundred six thousand, eight hundred twenty".