216679445 has 18 divisors (see below), whose sum is σ = 270482082. Its totient is φ = 166628896.

The previous prime is 216679409. The next prime is 216679453. The reversal of 216679445 is 544976612.

It can be written as a sum of positive squares in 3 ways, for example, as 24940036 + 191739409 = 4994^2 + 13847^2 .

It is not a de Polignac number, because 216679445 - 2⁸ = 216679189 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 216679396 and 216679405.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 954422 + ... + 954648.

Almost surely, 2^216679445 is an apocalyptic number.

It is an amenable number.

216679445 is a deficient number, since it is larger than the sum of its proper divisors (53802637).

216679445 is an frugal number, since it uses more digits than its factorization.

216679445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 517 (or 261 counting only the distinct ones).

The product of its digits is 362880, while the sum is 44.

The square root of 216679445 is about 14720.0354958811. The cubic root of 216679445 is about 600.6284572467.

The spelling of 216679445 in words is "two hundred sixteen million, six hundred seventy-nine thousand, four hundred forty-five".