166637129 has 4 divisors (see below), whose sum is σ = 168166020. Its totient is φ = 165108240.

The previous prime is 166637113. The next prime is 166637147. The reversal of 166637129 is 921736661.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 60031504 + 106605625 = 7748^2 + 10325^2 .

It is a cyclic number.

It is not a de Polignac number, because 166637129 - 2⁴ = 166637113 is a prime.

It is a super-2 number, since 2×166637129² = 55535865522725282, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166637189) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 764282 + ... + 764499.

It is an arithmetic number, because the mean of its divisors is an integer number (42041505).

Almost surely, 2^166637129 is an apocalyptic number.

It is an amenable number.

166637129 is a deficient number, since it is larger than the sum of its proper divisors (1528891).

166637129 is a wasteful number, since it uses less digits than its factorization.

166637129 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1528890.

The product of its digits is 81648, while the sum is 41.

The square root of 166637129 is about 12908.8004477566. The cubic root of 166637129 is about 550.2886958195.

The spelling of 166637129 in words is "one hundred sixty-six million, six hundred thirty-seven thousand, one hundred twenty-nine".