166121718 has 16 divisors (see below), whose sum is σ = 379706880. Its totient is φ = 47463336.

The previous prime is 166121713. The next prime is 166121723. The reversal of 166121718 is 817121661.

It is a happy number.

166121718 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (166121713) and next prime (166121723).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166121713) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1977598 + ... + 1977681.

It is an arithmetic number, because the mean of its divisors is an integer number (23731680).

Almost surely, 2^166121718 is an apocalyptic number.

166121718 is an abundant number, since it is smaller than the sum of its proper divisors (213585162).

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

166121718 is a wasteful number, since it uses less digits than its factorization.

166121718 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3955291.

The product of its digits is 4032, while the sum is 33.

The square root of 166121718 is about 12888.8214356472. The cubic root of 166121718 is about 549.7207596283.

The spelling of 166121718 in words is "one hundred sixty-six million, one hundred twenty-one thousand, seven hundred eighteen".