64516381 has 8 divisors (see below), whose sum is σ = 68449280. Its totient is φ = 60637248.

The previous prime is 64516379. The next prime is 64516409. The reversal of 64516381 is 18361546.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 64516381 - 2¹ = 64516379 is a prime.

It is a super-2 number, since 2×64516381² = 8324726834674322, 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 (64516181) 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, 10956 + ... + 15781.

It is an arithmetic number, because the mean of its divisors is an integer number (8556160).

Almost surely, 2^64516381 is an apocalyptic number.

It is an amenable number.

64516381 is a deficient number, since it is larger than the sum of its proper divisors (3932899).

64516381 is a wasteful number, since it uses less digits than its factorization.

64516381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26883.

The product of its digits is 17280, while the sum is 34.

The square root of 64516381 is about 8032.2089738751. The cubic root of 64516381 is about 401.0729133194.

The spelling of 64516381 in words is "sixty-four million, five hundred sixteen thousand, three hundred eighty-one".