64766539821 has 8 divisors (see below), whose sum is σ = 86375871520. Its totient is φ = 43167450672.

The previous prime is 64766539819. The next prime is 64766539841. The reversal of 64766539821 is 12893566746.

64766539821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 64766539821 - 2¹ = 64766539819 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 (64766539841) 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, 2545870 + ... + 2571183.

It is an arithmetic number, because the mean of its divisors is an integer number (10796983940).

Almost surely, 2^64766539821 is an apocalyptic number.

It is an amenable number.

64766539821 is a deficient number, since it is larger than the sum of its proper divisors (21609331699).

64766539821 is a wasteful number, since it uses less digits than its factorization.

64766539821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5121275.

The product of its digits is 13063680, while the sum is 57.

The spelling of 64766539821 in words is "sixty-four billion, seven hundred sixty-six million, five hundred thirty-nine thousand, eight hundred twenty-one".