212751397 has 4 divisors (see below), whose sum is σ = 213055596. Its totient is φ = 212447200.

The previous prime is 212751391. The next prime is 212751431. The reversal of 212751397 is 793157212.

It is a Cunningham number, because it is equal to 14586²+1.

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 183494116 + 29257281 = 13546^2 + 5409^2 .

It is a cyclic number.

It is not a de Polignac number, because 212751397 - 2³ = 212751389 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 (212751391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 151048 + ... + 152449.

It is an arithmetic number, because the mean of its divisors is an integer number (53263899).

Almost surely, 2^212751397 is an apocalyptic number.

It is an amenable number.

212751397 is a deficient number, since it is larger than the sum of its proper divisors (304199).

212751397 is an equidigital number, since it uses as much as digits as its factorization.

212751397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 304198.

The product of its digits is 26460, while the sum is 37.

The square root of 212751397 is about 14586.0000342794. Note that the first 4 decimals coincide. The cubic root of 212751397 is about 596.9768272203.

The spelling of 212751397 in words is "two hundred twelve million, seven hundred fifty-one thousand, three hundred ninety-seven".