64788557 has 4 divisors (see below), whose sum is σ = 64804800. Its totient is φ = 64772316.

The previous prime is 64788553. The next prime is 64788599. The reversal of 64788557 is 75588746.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 75588746 = 2 ⋅37794373.

It is a cyclic number.

It is not a de Polignac number, because 64788557 - 2² = 64788553 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64788553) 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, 2444 + ... + 11642.

It is an arithmetic number, because the mean of its divisors is an integer number (16201200).

Almost surely, 2^64788557 is an apocalyptic number.

It is an amenable number.

64788557 is a deficient number, since it is larger than the sum of its proper divisors (16243).

64788557 is an equidigital number, since it uses as much as digits as its factorization.

64788557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16242.

The product of its digits is 1881600, while the sum is 50.

The square root of 64788557 is about 8049.1339285665. The cubic root of 64788557 is about 401.6361256907.

The spelling of 64788557 in words is "sixty-four million, seven hundred eighty-eight thousand, five hundred fifty-seven".