64864821 has 8 divisors (see below), whose sum is σ = 98841664. Its totient is φ = 37065600.

The previous prime is 64864817. The next prime is 64864823. The reversal of 64864821 is 12846846.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 64864821 - 2² = 64864817 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 64864821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64864823) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1544380 + ... + 1544421.

It is an arithmetic number, because the mean of its divisors is an integer number (12355208).

Almost surely, 2^64864821 is an apocalyptic number.

It is an amenable number.

64864821 is a deficient number, since it is larger than the sum of its proper divisors (33976843).

64864821 is a wasteful number, since it uses less digits than its factorization.

64864821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3088811.

The product of its digits is 73728, while the sum is 39.

The square root of 64864821 is about 8053.8699393521. The cubic root of 64864821 is about 401.7936553955.

The spelling of 64864821 in words is "sixty-four million, eight hundred sixty-four thousand, eight hundred twenty-one".