71605001 has 4 divisors (see below), whose sum is σ = 77113092. Its totient is φ = 66096912.

The previous prime is 71604997. The next prime is 71605007. The reversal of 71605001 is 10050617.

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 31091776 + 40513225 = 5576^2 + 6365^2 .

It is a cyclic number.

It is not a de Polignac number, because 71605001 - 2² = 71604997 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (71605007) 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, 2754026 + ... + 2754051.

It is an arithmetic number, because the mean of its divisors is an integer number (19278273).

Almost surely, 2^71605001 is an apocalyptic number.

It is an amenable number.

71605001 is a deficient number, since it is larger than the sum of its proper divisors (5508091).

71605001 is a wasteful number, since it uses less digits than its factorization.

71605001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5508090.

The product of its (nonzero) digits is 210, while the sum is 20.

The square root of 71605001 is about 8461.9738241146. The cubic root of 71605001 is about 415.2545996639.

Adding to 71605001 its reverse (10050617), we get a palindrome (81655618).

The spelling of 71605001 in words is "seventy-one million, six hundred five thousand, one".