213345657 has 50 divisors (see below), whose sum is σ = 372135258. Its totient is φ = 121800672.

The previous prime is 213345653. The next prime is 213345697. The reversal of 213345657 is 756543312.

It can be written as a sum of positive squares in only one way, i.e., 163558521 + 49787136 = 12789^2 + 7056^2 .

It is not a de Polignac number, because 213345657 - 2² = 213345653 is a prime.

It is not an unprimeable number, because it can be changed into a prime (213345653) 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 49 ways as a sum of consecutive naturals, for example, 193933 + ... + 195029.

Almost surely, 2^213345657 is an apocalyptic number.

213345657 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

213345657 is a deficient number, since it is larger than the sum of its proper divisors (158789601).

213345657 is an frugal number, since it uses more digits than its factorization.

213345657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1137 (or 1107 counting only the distinct ones).

The product of its digits is 75600, while the sum is 36.

The square root of 213345657 is about 14606.3567326010. The cubic root of 213345657 is about 597.5321383482.

Adding to 213345657 its reverse (756543312), we get a palindrome (969888969).

The spelling of 213345657 in words is "two hundred thirteen million, three hundred forty-five thousand, six hundred fifty-seven".