215861216 has 12 divisors (see below), whose sum is σ = 424976832. Its totient is φ = 107930592.

The previous prime is 215861213. The next prime is 215861227. The reversal of 215861216 is 612168512.

It is a Harshad number since it is a multiple of its sum of digits (32), and also a Moran number because the ratio is a prime number: 6745663 = 215861216 / (2 + 1 + 5 + 8 + 6 + 1 + 2 + 1 + 6).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215861213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3372800 + ... + 3372863.

It is an arithmetic number, because the mean of its divisors is an integer number (35414736).

Almost surely, 2^215861216 is an apocalyptic number.

It is an amenable number.

215861216 is a deficient number, since it is larger than the sum of its proper divisors (209115616).

215861216 is an equidigital number, since it uses as much as digits as its factorization.

215861216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6745673 (or 6745665 counting only the distinct ones).

The product of its digits is 5760, while the sum is 32.

The square root of 215861216 is about 14692.2161704761. The cubic root of 215861216 is about 599.8714687645.

The spelling of 215861216 in words is "two hundred fifteen million, eight hundred sixty-one thousand, two hundred sixteen".