166216415 has 4 divisors (see below), whose sum is σ = 199459704. Its totient is φ = 132973128.

The previous prime is 166216411. The next prime is 166216417. The reversal of 166216415 is 514612661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 514612661 = 17 ⋅30271333.

It is a cyclic number.

It is not a de Polignac number, because 166216415 - 2² = 166216411 is a prime.

It is a super-3 number, since 3×166216415³ (a number of 26 digits) contains 333 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 (166216411) 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, 16621637 + ... + 16621646.

It is an arithmetic number, because the mean of its divisors is an integer number (49864926).

Almost surely, 2^166216415 is an apocalyptic number.

166216415 is a deficient number, since it is larger than the sum of its proper divisors (33243289).

166216415 is an equidigital number, since it uses as much as digits as its factorization.

166216415 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33243288.

The product of its digits is 8640, while the sum is 32.

The square root of 166216415 is about 12892.4945220078. The cubic root of 166216415 is about 549.8251951369.

The spelling of 166216415 in words is "one hundred sixty-six million, two hundred sixteen thousand, four hundred fifteen".