64693439646 has 96 divisors (see below), whose sum is σ = 144476150784. Its totient is φ = 19294070400.

The previous prime is 64693439639. The next prime is 64693439647.

64693439646 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×64693439646² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 64693439646.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64693439647) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 32168781 + ... + 32170791.

It is an arithmetic number, because the mean of its divisors is an integer number (1504959904).

Almost surely, 2^64693439646 is an apocalyptic number.

64693439646 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 64693439646, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72238075392).

64693439646 is an abundant number, since it is smaller than the sum of its proper divisors (79782711138).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

64693439646 is a wasteful number, since it uses less digits than its factorization.

64693439646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2718 (or 2707 counting only the distinct ones).

The product of its digits is 60466176, while the sum is 60.

The spelling of 64693439646 in words is "sixty-four billion, six hundred ninety-three million, four hundred thirty-nine thousand, six hundred forty-six".