213240551 has 4 divisors (see below), whose sum is σ = 217777632. Its totient is φ = 208703472.

The previous prime is 213240523. The next prime is 213240557. The reversal of 213240551 is 155042312.

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

It is a cyclic number.

It is not a de Polignac number, because 213240551 - 2⁶ = 213240487 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 (213240557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2268470 + ... + 2268563.

It is an arithmetic number, because the mean of its divisors is an integer number (54444408).

Almost surely, 2^213240551 is an apocalyptic number.

213240551 is a deficient number, since it is larger than the sum of its proper divisors (4537081).

213240551 is an equidigital number, since it uses as much as digits as its factorization.

213240551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4537080.

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 213240551 is about 14602.7583353283. The cubic root of 213240551 is about 597.4339963155.

Adding to 213240551 its reverse (155042312), we get a palindrome (368282863).

The spelling of 213240551 in words is "two hundred thirteen million, two hundred forty thousand, five hundred fifty-one".