215666202106 has 32 divisors (see below), whose sum is σ = 334250737920. Its totient is φ = 104304135936.

The previous prime is 215666202071. The next prime is 215666202107. The reversal of 215666202106 is 601202666512.

It is a super-4 number, since 4×215666202106⁴ (a number of 46 digits) contains 4444 as substring.

It is not an unprimeable number, because it can be changed into a prime (215666202107) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23227741 + ... + 23237023.

It is an arithmetic number, because the mean of its divisors is an integer number (10445335560).

Almost surely, 2^215666202106 is an apocalyptic number.

215666202106 is a deficient number, since it is larger than the sum of its proper divisors (118584535814).

215666202106 is a wasteful number, since it uses less digits than its factorization.

215666202106 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12198.

The product of its (nonzero) digits is 51840, while the sum is 37.

Adding to 215666202106 its reverse (601202666512), we get a palindrome (816868868618).

The spelling of 215666202106 in words is "two hundred fifteen billion, six hundred sixty-six million, two hundred two thousand, one hundred six".