64809638 has 4 divisors (see below), whose sum is σ = 97214460. Its totient is φ = 32404818.

The previous prime is 64809629. The next prime is 64809659. The reversal of 64809638 is 83690846.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 83690846 = 2 ⋅41845423.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16202408 + ... + 16202411.

It is an arithmetic number, because the mean of its divisors is an integer number (24303615).

Almost surely, 2^64809638 is an apocalyptic number.

64809638 is a deficient number, since it is larger than the sum of its proper divisors (32404822).

64809638 is a wasteful number, since it uses less digits than its factorization.

64809638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32404821.

The product of its (nonzero) digits is 248832, while the sum is 44.

The square root of 64809638 is about 8050.4433418291. The cubic root of 64809638 is about 401.6796826262.

The spelling of 64809638 in words is "sixty-four million, eight hundred nine thousand, six hundred thirty-eight".