66736232640 has 448 divisors, whose sum is σ = 293526789120. Its totient is φ = 13867130880.

The previous prime is 66736232623. The next prime is 66736232683. The reversal of 66736232640 is 4623263766.

It is a tau number, because it is divible by the number of its divisors (448).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 615124 + ... + 715436.

Almost surely, 2^66736232640 is an apocalyptic number.

66736232640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66736232640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (146763394560).

66736232640 is an abundant number, since it is smaller than the sum of its proper divisors (226790556480).

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

66736232640 is a wasteful number, since it uses less digits than its factorization.

66736232640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100357 (or 100341 counting only the distinct ones).

The product of its (nonzero) digits is 1306368, while the sum is 45.

The spelling of 66736232640 in words is "sixty-six billion, seven hundred thirty-six million, two hundred thirty-two thousand, six hundred forty".