166746137381 has 4 divisors (see below), whose sum is σ = 168755127072. Its totient is φ = 164737147692.

The previous prime is 166746137377. The next prime is 166746137387. The reversal of 166746137381 is 183731647661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 166746137381 - 2² = 166746137377 is a prime.

It is a super-2 number, since 2×166746137381² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166746137387) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1004494721 + ... + 1004494886.

It is an arithmetic number, because the mean of its divisors is an integer number (42188781768).

Almost surely, 2^166746137381 is an apocalyptic number.

It is an amenable number.

166746137381 is a deficient number, since it is larger than the sum of its proper divisors (2008989691).

166746137381 is an equidigital number, since it uses as much as digits as its factorization.

166746137381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2008989690.

The product of its digits is 3048192, while the sum is 53.

The spelling of 166746137381 in words is "one hundred sixty-six billion, seven hundred forty-six million, one hundred thirty-seven thousand, three hundred eighty-one".