65383781 has 4 divisors (see below), whose sum is σ = 65400000. Its totient is φ = 65367564.

The previous prime is 65383763. The next prime is 65383811. The reversal of 65383781 is 18738356.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-65383781 is a prime.

It is a super-2 number, since 2×65383781² = 8550077635711922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65383711) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3140 + ... + 11858.

It is an arithmetic number, because the mean of its divisors is an integer number (16350000).

Almost surely, 2^65383781 is an apocalyptic number.

It is an amenable number.

65383781 is a deficient number, since it is larger than the sum of its proper divisors (16219).

65383781 is an equidigital number, since it uses as much as digits as its factorization.

65383781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16218.

The product of its digits is 120960, while the sum is 41.

The square root of 65383781 is about 8086.0238065442. The cubic root of 65383781 is about 402.8623456697.

The spelling of 65383781 in words is "sixty-five million, three hundred eighty-three thousand, seven hundred eighty-one".