666158681216 has 64 divisors (see below), whose sum is σ = 1517201350080. Its totient is φ = 285402313728.

The previous prime is 666158681191. The next prime is 666158681273. The reversal of 666158681216 is 612186851666.

It is a tau number, because it is divible by the number of its divisors (64).

It is a super-2 number, since 2×666158681216² (a number of 24 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (56).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2626826 + ... + 2869238.

It is an arithmetic number, because the mean of its divisors is an integer number (23706271095).

Almost surely, 2^666158681216 is an apocalyptic number.

It is an amenable number.

666158681216 is an abundant number, since it is smaller than the sum of its proper divisors (851042668864).

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

666158681216 is a wasteful number, since it uses less digits than its factorization.

666158681216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 245501 (or 245489 counting only the distinct ones).

The product of its digits is 4976640, while the sum is 56.

The spelling of 666158681216 in words is "six hundred sixty-six billion, one hundred fifty-eight million, six hundred eighty-one thousand, two hundred sixteen".