71663197 has 4 divisors (see below), whose sum is σ = 71747676. Its totient is φ = 71578720.

The previous prime is 71663167. The next prime is 71663201. The reversal of 71663197 is 79136617.

It is a happy number.

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 69572281 + 2090916 = 8341^2 + 1446^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71663197 is a prime.

It is a super-2 number, since 2×71663197² = 10271227608521618, which contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71663107) 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, 40954 + ... + 42667.

It is an arithmetic number, because the mean of its divisors is an integer number (17936919).

Almost surely, 2^71663197 is an apocalyptic number.

It is an amenable number.

71663197 is a deficient number, since it is larger than the sum of its proper divisors (84479).

71663197 is an equidigital number, since it uses as much as digits as its factorization.

71663197 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84478.

The product of its digits is 47628, while the sum is 40.

The square root of 71663197 is about 8465.4118033324. The cubic root of 71663197 is about 415.3670667281.

The spelling of 71663197 in words is "seventy-one million, six hundred sixty-three thousand, one hundred ninety-seven".