64964781 has 64 divisors (see below), whose sum is σ = 117760000. Its totient is φ = 34572096.

The previous prime is 64964777. The next prime is 64964831. The reversal of 64964781 is 18746946.

It is not a de Polignac number, because 64964781 - 2² = 64964777 is a prime.

It is a super-2 number, since 2×64964781² = 8440845540755922, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64964761) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 283575 + ... + 283803.

It is an arithmetic number, because the mean of its divisors is an integer number (1840000).

Almost surely, 2^64964781 is an apocalyptic number.

It is an amenable number.

64964781 is a deficient number, since it is larger than the sum of its proper divisors (52795219).

64964781 is a wasteful number, since it uses less digits than its factorization.

64964781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 343 (or 337 counting only the distinct ones).

The product of its digits is 290304, while the sum is 45.

The square root of 64964781 is about 8060.0732626943. The cubic root of 64964781 is about 401.9999443083. Note that the first 4 decimals are identical.

The spelling of 64964781 in words is "sixty-four million, nine hundred sixty-four thousand, seven hundred eighty-one".