66156217072 has 40 divisors (see below), whose sum is σ = 145909768320. Its totient is φ = 28763570880.

The previous prime is 66156217063. The next prime is 66156217081. The reversal of 66156217072 is 27071265166.

It is an interprime number because it is at equal distance from previous prime (66156217063) and next prime (66156217081).

It is a congruent number.

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, 8167422 + ... + 8175517.

It is an arithmetic number, because the mean of its divisors is an integer number (3647744208).

Almost surely, 2^66156217072 is an apocalyptic number.

It is an amenable number.

66156217072 is an abundant number, since it is smaller than the sum of its proper divisors (79753551248).

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

66156217072 is a wasteful number, since it uses less digits than its factorization.

66156217072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16342981 (or 16342975 counting only the distinct ones).

The product of its (nonzero) digits is 211680, while the sum is 43.

The spelling of 66156217072 in words is "sixty-six billion, one hundred fifty-six million, two hundred seventeen thousand, seventy-two".