64551649 has 4 divisors (see below), whose sum is σ = 64962964. Its totient is φ = 64140336.

The previous prime is 64551647. The next prime is 64551667. The reversal of 64551649 is 94615546.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 39150049 + 25401600 = 6257^2 + 5040^2 .

It is a cyclic number.

It is not a de Polignac number, because 64551649 - 2¹ = 64551647 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64551647) 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, 205422 + ... + 205735.

It is an arithmetic number, because the mean of its divisors is an integer number (16240741).

Almost surely, 2^64551649 is an apocalyptic number.

It is an amenable number.

64551649 is a deficient number, since it is larger than the sum of its proper divisors (411315).

64551649 is a wasteful number, since it uses less digits than its factorization.

64551649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 411314.

The product of its digits is 129600, while the sum is 40.

The square root of 64551649 is about 8034.4040849337. The cubic root of 64551649 is about 401.1459824253.

The spelling of 64551649 in words is "sixty-four million, five hundred fifty-one thousand, six hundred forty-nine".