216451995 has 16 divisors (see below), whose sum is σ = 346770720. Its totient is φ = 115291904.

The previous prime is 216451993. The next prime is 216451999. The reversal of 216451995 is 599154612.

It is a cyclic number.

It is not a de Polignac number, because 216451995 - 2¹ = 216451993 is a prime.

It is a super-2 number, since 2×216451995² = 93702932278960050, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (216451993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3217 + ... + 21053.

It is an arithmetic number, because the mean of its divisors is an integer number (21673170).

Almost surely, 2^216451995 is an apocalyptic number.

216451995 is a deficient number, since it is larger than the sum of its proper divisors (130318725).

216451995 is a wasteful number, since it uses less digits than its factorization.

216451995 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18654.

The product of its digits is 97200, while the sum is 42.

The square root of 216451995 is about 14712.3076028202. The cubic root of 216451995 is about 600.4182223047.

The spelling of 216451995 in words is "two hundred sixteen million, four hundred fifty-one thousand, nine hundred ninety-five".