64457081 has 8 divisors (see below), whose sum is σ = 73498824. Its totient is φ = 55998720.

The previous prime is 64457077. The next prime is 64457083. The reversal of 64457081 is 18075446.

It can be written as a sum of positive squares in 4 ways, for example, as 1175056 + 63282025 = 1084^2 + 7955^2 .

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 64457081 - 2² = 64457077 is a prime.

It is a super-2 number, since 2×64457081² = 8309430582081122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64457083) 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, 145610 + ... + 146051.

It is an arithmetic number, because the mean of its divisors is an integer number (9187353).

Almost surely, 2^64457081 is an apocalyptic number.

It is an amenable number.

64457081 is a deficient number, since it is larger than the sum of its proper divisors (9041743).

64457081 is a wasteful number, since it uses less digits than its factorization.

64457081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 291691.

The product of its (nonzero) digits is 26880, while the sum is 35.

The square root of 64457081 is about 8028.5167372311. The cubic root of 64457081 is about 400.9499940753.

The spelling of 64457081 in words is "sixty-four million, four hundred fifty-seven thousand, eighty-one".