64376781 has 32 divisors (see below), whose sum is σ = 104259840. Its totient is φ = 34546176.

The previous prime is 64376761. The next prime is 64376797. The reversal of 64376781 is 18767346.

It is not a de Polignac number, because 64376781 - 2⁶ = 64376717 is a prime.

It is a super-2 number, since 2×64376781² = 8288739863843922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64376761) 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 31 ways as a sum of consecutive naturals, for example, 21105 + ... + 23961.

It is an arithmetic number, because the mean of its divisors is an integer number (3258120).

Almost surely, 2^64376781 is an apocalyptic number.

It is an amenable number.

64376781 is a deficient number, since it is larger than the sum of its proper divisors (39883059).

64376781 is a wasteful number, since it uses less digits than its factorization.

64376781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2933.

The product of its digits is 169344, while the sum is 42.

The square root of 64376781 is about 8023.5142549883. The cubic root of 64376781 is about 400.7834250280.

The spelling of 64376781 in words is "sixty-four million, three hundred seventy-six thousand, seven hundred eighty-one".