64764821 has 4 divisors (see below), whose sum is σ = 70652544. Its totient is φ = 58877100.

The previous prime is 64764811. The next prime is 64764827. The reversal of 64764821 is 12846746.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64764821 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64764827) 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, 2943845 + ... + 2943866.

It is an arithmetic number, because the mean of its divisors is an integer number (17663136).

Almost surely, 2^64764821 is an apocalyptic number.

It is an amenable number.

64764821 is a deficient number, since it is larger than the sum of its proper divisors (5887723).

64764821 is a wasteful number, since it uses less digits than its factorization.

64764821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5887722.

The product of its digits is 64512, while the sum is 38.

The square root of 64764821 is about 8047.6593491524. The cubic root of 64764821 is about 401.5870717632.

The spelling of 64764821 in words is "sixty-four million, seven hundred sixty-four thousand, eight hundred twenty-one".