64539000781 has 8 divisors (see below), whose sum is σ = 67559228928. Its totient is φ = 61577418000.

The previous prime is 64539000769. The next prime is 64539000793. The reversal of 64539000781 is 18700093546.

It is an interprime number because it is at equal distance from previous prime (64539000769) and next prime (64539000793).

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

It is a cyclic number.

It is not a de Polignac number, because 64539000781 - 2⁵ = 64539000749 is a prime.

It is a super-2 number, since 2×64539000781² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64539001781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14659090 + ... + 14663491.

It is an arithmetic number, because the mean of its divisors is an integer number (8444903616).

Almost surely, 2^64539000781 is an apocalyptic number.

64539000781 is the 113613-rd centered decagonal number.

It is an amenable number.

64539000781 is a deficient number, since it is larger than the sum of its proper divisors (3020228147).

64539000781 is a wasteful number, since it uses less digits than its factorization.

64539000781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29322683.

The product of its (nonzero) digits is 181440, while the sum is 43.

The spelling of 64539000781 in words is "sixty-four billion, five hundred thirty-nine million, seven hundred eighty-one", and thus it is an aban number.