212647705 has 4 divisors (see below), whose sum is σ = 255177252. Its totient is φ = 170118160.

The previous prime is 212647667. The next prime is 212647717. The reversal of 212647705 is 507746212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 115605504 + 97042201 = 10752^2 + 9851^2 .

It is a de Polignac number, because none of the positive numbers 2^k-212647705 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21264766 + ... + 21264775.

It is an arithmetic number, because the mean of its divisors is an integer number (63794313).

Almost surely, 2^212647705 is an apocalyptic number.

It is an amenable number.

212647705 is a deficient number, since it is larger than the sum of its proper divisors (42529547).

212647705 is an equidigital number, since it uses as much as digits as its factorization.

212647705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42529546.

The product of its (nonzero) digits is 23520, while the sum is 34.

The square root of 212647705 is about 14582.4450967593. The cubic root of 212647705 is about 596.8798254592.

The spelling of 212647705 in words is "two hundred twelve million, six hundred forty-seven thousand, seven hundred five".