166861755 has 32 divisors (see below), whose sum is σ = 302253120. Its totient is φ = 87310080.

The previous prime is 166861741. The next prime is 166861769. The reversal of 166861755 is 557168661.

It is an interprime number because it is at equal distance from previous prime (166861741) and next prime (166861769).

It is not a de Polignac number, because 166861755 - 2²¹ = 164764603 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 166861755.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 4506 + ... + 18815.

It is an arithmetic number, because the mean of its divisors is an integer number (9445410).

Almost surely, 2^166861755 is an apocalyptic number.

166861755 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

166861755 is a deficient number, since it is larger than the sum of its proper divisors (135391365).

166861755 is a wasteful number, since it uses less digits than its factorization.

166861755 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23388 (or 23382 counting only the distinct ones).

The product of its digits is 302400, while the sum is 45.

The square root of 166861755 is about 12917.4980162569. The cubic root of 166861755 is about 550.5358469184.

The spelling of 166861755 in words is "one hundred sixty-six million, eight hundred sixty-one thousand, seven hundred fifty-five".