64781289 has 20 divisors (see below), whose sum is σ = 99897600. Its totient is φ = 41792760.

The previous prime is 64781257. The next prime is 64781309. The reversal of 64781289 is 98218746.

It is not a de Polignac number, because 64781289 - 2⁵ = 64781257 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64781209) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 10389 + ... + 15410.

It is an arithmetic number, because the mean of its divisors is an integer number (4994880).

Almost surely, 2^64781289 is an apocalyptic number.

It is an amenable number.

64781289 is a deficient number, since it is larger than the sum of its proper divisors (35116311).

64781289 is a wasteful number, since it uses less digits than its factorization.

64781289 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25842 (or 25833 counting only the distinct ones).

The product of its digits is 193536, while the sum is 45.

The square root of 64781289 is about 8048.6824387598. The cubic root of 64781289 is about 401.6211065748.

The spelling of 64781289 in words is "sixty-four million, seven hundred eighty-one thousand, two hundred eighty-nine".