212661653 has 4 divisors (see below), whose sum is σ = 225171180. Its totient is φ = 200152128.

The previous prime is 212661637. The next prime is 212661671. The reversal of 212661653 is 356166212.

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 118222129 + 94439524 = 10873^2 + 9718^2 .

It is a cyclic number.

It is not a de Polignac number, because 212661653 - 2⁴ = 212661637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212661353) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6254738 + ... + 6254771.

It is an arithmetic number, because the mean of its divisors is an integer number (56292795).

Almost surely, 2^212661653 is an apocalyptic number.

It is an amenable number.

212661653 is a deficient number, since it is larger than the sum of its proper divisors (12509527).

212661653 is a wasteful number, since it uses less digits than its factorization.

212661653 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12509526.

The product of its digits is 12960, while the sum is 32.

The square root of 212661653 is about 14582.9233351890. The cubic root of 212661653 is about 596.8928753654.

The spelling of 212661653 in words is "two hundred twelve million, six hundred sixty-one thousand, six hundred fifty-three".