215981275 has 6 divisors (see below), whose sum is σ = 267816812. Its totient is φ = 172785000.

The previous prime is 215981263. The next prime is 215981287. The reversal of 215981275 is 572189512.

It is an interprime number because it is at equal distance from previous prime (215981263) and next prime (215981287).

It is not a de Polignac number, because 215981275 - 2⁹ = 215980763 is a prime.

It is a super-2 number, since 2×215981275² = 93295822301251250, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4319601 + ... + 4319650.

Almost surely, 2^215981275 is an apocalyptic number.

215981275 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

215981275 is a deficient number, since it is larger than the sum of its proper divisors (51835537).

215981275 is an equidigital number, since it uses as much as digits as its factorization.

215981275 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8639261 (or 8639256 counting only the distinct ones).

The product of its digits is 50400, while the sum is 40.

The square root of 215981275 is about 14696.3014054557. The cubic root of 215981275 is about 599.9826615360.

The spelling of 215981275 in words is "two hundred fifteen million, nine hundred eighty-one thousand, two hundred seventy-five".