64661142784 has 36 divisors (see below), whose sum is σ = 147508236064. Its totient is φ = 27711917568.

The previous prime is 64661142709. The next prime is 64661142853. The reversal of 64661142784 is 48724116646.

It is a super-2 number, since 2×64661142784² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18039822 + ... + 18043405.

Almost surely, 2^64661142784 is an apocalyptic number.

64661142784 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

64661142784 is an abundant number, since it is smaller than the sum of its proper divisors (82847093280).

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

64661142784 is an equidigital number, since it uses as much as digits as its factorization.

64661142784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36083250 (or 36083236 counting only the distinct ones).

The product of its digits is 1548288, while the sum is 49.

The spelling of 64661142784 in words is "sixty-four billion, six hundred sixty-one million, one hundred forty-two thousand, seven hundred eighty-four".