64642455 has 40 divisors (see below), whose sum is σ = 116618832. Its totient is φ = 34255872.

The previous prime is 64642453. The next prime is 64642463. The reversal of 64642455 is 55424646.

64642455 is a `hidden beast` number, since 6 + 4 + 642 + 4 + 5 + 5 = 666.

It is not a de Polignac number, because 64642455 - 2¹ = 64642453 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64642451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 77752 + ... + 78578.

Almost surely, 2^64642455 is an apocalyptic number.

64642455 is a deficient number, since it is larger than the sum of its proper divisors (51976377).

64642455 is a wasteful number, since it uses less digits than its factorization.

64642455 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1037 (or 1028 counting only the distinct ones).

The product of its digits is 115200, while the sum is 36.

The square root of 64642455 is about 8040.0531714660. The cubic root of 64642455 is about 401.3339941203. Note that the first 3 decimals are identical.

The spelling of 64642455 in words is "sixty-four million, six hundred forty-two thousand, four hundred fifty-five".