66619238400 has 1152 divisors, whose sum is σ = 288337795200. Its totient is φ = 14863564800.

The previous prime is 66619238383. The next prime is 66619238417. The reversal of 66619238400 is 483291666.

It is an interprime number because it is at equal distance from previous prime (66619238383) and next prime (66619238417).

It is a tau number, because it is divible by the number of its divisors (1152).

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 197683032 + ... + 197683368.

It is an arithmetic number, because the mean of its divisors is an integer number (250293225).

Almost surely, 2^66619238400 is an apocalyptic number.

66619238400 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 66619238400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (144168897600).

66619238400 is an abundant number, since it is smaller than the sum of its proper divisors (221718556800).

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

66619238400 is a wasteful number, since it uses less digits than its factorization.

66619238400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 402 (or 371 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 45.

The spelling of 66619238400 in words is "sixty-six billion, six hundred nineteen million, two hundred thirty-eight thousand, four hundred".