215919966 has 16 divisors (see below), whose sum is σ = 432086544. Its totient is φ = 71932224.

The previous prime is 215919947. The next prime is 215919967. The reversal of 215919966 is 669919512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215919967) 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, 2290 + ... + 20906.

It is an arithmetic number, because the mean of its divisors is an integer number (27005409).

Almost surely, 2^215919966 is an apocalyptic number.

215919966 is an abundant number, since it is smaller than the sum of its proper divisors (216166578).

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

215919966 is a wasteful number, since it uses less digits than its factorization.

215919966 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20555.

The product of its digits is 262440, while the sum is 48.

The square root of 215919966 is about 14694.2153924597. The cubic root of 215919966 is about 599.9258852898.

The spelling of 215919966 in words is "two hundred fifteen million, nine hundred nineteen thousand, nine hundred sixty-six".