66726402963840 has 1280 divisors, whose sum is σ = 247179651840000. Its totient is φ = 17211576066048.

The previous prime is 66726402963817. The next prime is 66726402963863. The reversal of 66726402963840 is 4836920462766.

66726402963840 is a `hidden beast` number, since 6 + 6 + 7 + 264 + 0 + 296 + 3 + 84 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (66726402963817) and next prime (66726402963863).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 111396331861 + ... + 111396332459.

It is an arithmetic number, because the mean of its divisors is an integer number (193109103000).

Almost surely, 2^{66726402963840} is an apocalyptic number.

66726402963840 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 66726402963840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (123589825920000).

66726402963840 is an abundant number, since it is smaller than the sum of its proper divisors (180453248876160).

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

66726402963840 is an frugal number, since it uses more digits than its factorization.

66726402963840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 921 (or 885 counting only the distinct ones).

The product of its (nonzero) digits is 125411328, while the sum is 63.

The spelling of 66726402963840 in words is "sixty-six trillion, seven hundred twenty-six billion, four hundred two million, nine hundred sixty-three thousand, eight hundred forty".