213780394 has 4 divisors (see below), whose sum is σ = 320670594. Its totient is φ = 106890196.

The previous prime is 213780353. The next prime is 213780397. The reversal of 213780394 is 493087312.

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

It can be written as a sum of positive squares in only one way, i.e., 188650225 + 25130169 = 13735^2 + 5013^2 .

It is not an unprimeable number, because it can be changed into a prime (213780397) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 53445097 + ... + 53445100.

Almost surely, 2^213780394 is an apocalyptic number.

213780394 is a deficient number, since it is larger than the sum of its proper divisors (106890200).

213780394 is a wasteful number, since it uses less digits than its factorization.

213780394 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106890199.

The product of its (nonzero) digits is 36288, while the sum is 37.

The square root of 213780394 is about 14621.2309331328. The cubic root of 213780394 is about 597.9377291116.

The spelling of 213780394 in words is "two hundred thirteen million, seven hundred eighty thousand, three hundred ninety-four".