203216813 has 4 divisors (see below), whose sum is σ = 203388348. Its totient is φ = 203045280.

The previous prime is 203216809. The next prime is 203216831. The reversal of 203216813 is 318612302.

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 66373609 + 136843204 = 8147^2 + 11698^2 .

It is a cyclic number.

It is not a de Polignac number, because 203216813 - 2² = 203216809 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 (203216863) 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, 83978 + ... + 86363.

It is an arithmetic number, because the mean of its divisors is an integer number (50847087).

Almost surely, 2^203216813 is an apocalyptic number.

It is an amenable number.

203216813 is a deficient number, since it is larger than the sum of its proper divisors (171535).

203216813 is a wasteful number, since it uses less digits than its factorization.

203216813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171534.

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 203216813 is about 14255.4134629621. The cubic root of 203216813 is about 587.9222260115.

The spelling of 203216813 in words is "two hundred three million, two hundred sixteen thousand, eight hundred thirteen".