212685685 has 4 divisors (see below), whose sum is σ = 255222828. Its totient is φ = 170148544.

The previous prime is 212685673. The next prime is 212685701. The reversal of 212685685 is 586586212.

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 51065316 + 161620369 = 7146^2 + 12713^2 .

It is a cyclic number.

It is not a de Polignac number, because 212685685 - 2⁹ = 212685173 is a prime.

It is a Duffinian number.

It is a congruent 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, 21268564 + ... + 21268573.

It is an arithmetic number, because the mean of its divisors is an integer number (63805707).

Almost surely, 2^212685685 is an apocalyptic number.

It is an amenable number.

212685685 is a deficient number, since it is larger than the sum of its proper divisors (42537143).

212685685 is an equidigital number, since it uses as much as digits as its factorization.

212685685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42537142.

The product of its digits is 230400, while the sum is 43.

The square root of 212685685 is about 14583.7472893629. The cubic root of 212685685 is about 596.9153586372.

The spelling of 212685685 in words is "two hundred twelve million, six hundred eighty-five thousand, six hundred eighty-five".