166251380905 has 16 divisors (see below), whose sum is σ = 204939270144. Its totient is φ = 129377632320.

The previous prime is 166251380899. The next prime is 166251380909. The reversal of 166251380905 is 509083152661.

It is not a de Polignac number, because 166251380905 - 2¹³ = 166251372713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166251380909) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 751464 + ... + 947206.

It is an arithmetic number, because the mean of its divisors is an integer number (12808704384).

Almost surely, 2^166251380905 is an apocalyptic number.

It is an amenable number.

166251380905 is a deficient number, since it is larger than the sum of its proper divisors (38687889239).

166251380905 is a wasteful number, since it uses less digits than its factorization.

166251380905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 200376.

The product of its (nonzero) digits is 388800, while the sum is 46.

The spelling of 166251380905 in words is "one hundred sixty-six billion, two hundred fifty-one million, three hundred eighty thousand, nine hundred five".