66978213120 has 1440 divisors, whose sum is σ = 305811179520. Its totient is φ = 13616087040.

The previous prime is 66978213119. The next prime is 66978213121. The reversal of 66978213120 is 2131287966.

It is an interprime number because it is at equal distance from previous prime (66978213119) and next prime (66978213121).

It is a tau number, because it is divible by the number of its divisors (1440).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66978213121) by changing a digit.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 292481166 + ... + 292481394.

Almost surely, 2^66978213120 is an apocalyptic number.

66978213120 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 66978213120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (152905589760).

66978213120 is an abundant number, since it is smaller than the sum of its proper divisors (238832966400).

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

66978213120 is a wasteful number, since it uses less digits than its factorization.

66978213120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 313 (or 290 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 45.

The spelling of 66978213120 in words is "sixty-six billion, nine hundred seventy-eight million, two hundred thirteen thousand, one hundred twenty".