666398968950000 has 1920 divisors, whose sum is σ = 2688124637011968. Its totient is φ = 139751424000000.

The previous prime is 666398968949957. The next prime is 666398968950019. The reversal of 666398968950000 is 59869893666.

It is a Harshad number since it is a multiple of its sum of digits (75).

It is a junction number, because it is equal to n+sod(n) for n = 666398968949895 and 666398968949904.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 87880646209 + ... + 87880653791.

Almost surely, 2^{666398968950000} is an apocalyptic number.

666398968950000 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 666398968950000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1344062318505984).

666398968950000 is an abundant number, since it is smaller than the sum of its proper divisors (2021725668061968).

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

666398968950000 is a wasteful number, since it uses less digits than its factorization.

666398968950000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7901 (or 7875 counting only the distinct ones).

The product of its (nonzero) digits is 906992640, while the sum is 75.

The spelling of 666398968950000 in words is "six hundred sixty-six trillion, three hundred ninety-eight billion, nine hundred sixty-eight million, nine hundred fifty thousand".