206971897 has 4 divisors (see below), whose sum is σ = 225787536. Its totient is φ = 188156260.

The previous prime is 206971867. The next prime is 206971901. The reversal of 206971897 is 798179602.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 206971897 - 2¹⁵ = 206939129 is a prime.

It is a super-2 number, since 2×206971897² = 85674732295557218, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 206971897.

It is not an unprimeable number, because it can be changed into a prime (206971847) 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, 9407803 + ... + 9407824.

It is an arithmetic number, because the mean of its divisors is an integer number (56446884).

Almost surely, 2^206971897 is an apocalyptic number.

It is an amenable number.

206971897 is a deficient number, since it is larger than the sum of its proper divisors (18815639).

206971897 is a wasteful number, since it uses less digits than its factorization.

206971897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18815638.

The product of its (nonzero) digits is 381024, while the sum is 49.

The square root of 206971897 is about 14386.5178900247. The cubic root of 206971897 is about 591.5213985842.

The spelling of 206971897 in words is "two hundred six million, nine hundred seventy-one thousand, eight hundred ninety-seven".