64313781 has 8 divisors (see below), whose sum is σ = 98001984. Its totient is φ = 36750720.

The previous prime is 64313749. The next prime is 64313797. The reversal of 64313781 is 18731346.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 64313781 - 2⁵ = 64313749 is a prime.

It is a super-2 number, since 2×64313781² = 8272524853031922, which contains 22 as substring.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64313701) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1531260 + ... + 1531301.

It is an arithmetic number, because the mean of its divisors is an integer number (12250248).

Almost surely, 2^64313781 is an apocalyptic number.

It is an amenable number.

64313781 is a deficient number, since it is larger than the sum of its proper divisors (33688203).

64313781 is a wasteful number, since it uses less digits than its factorization.

64313781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3062571.

The product of its digits is 12096, while the sum is 33.

The square root of 64313781 is about 8019.5873335228. The cubic root of 64313781 is about 400.6526449739.

The spelling of 64313781 in words is "sixty-four million, three hundred thirteen thousand, seven hundred eighty-one".