71643021 has 8 divisors (see below), whose sum is σ = 98818080. Its totient is φ = 46114992.

The previous prime is 71643001. The next prime is 71643029. The reversal of 71643021 is 12034617.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 71643021 - 2¹⁷ = 71511949 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 71642982 and 71643000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71643029) 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 7 ways as a sum of consecutive naturals, for example, 411655 + ... + 411828.

It is an arithmetic number, because the mean of its divisors is an integer number (12352260).

Almost surely, 2^71643021 is an apocalyptic number.

It is an amenable number.

71643021 is a deficient number, since it is larger than the sum of its proper divisors (27175059).

71643021 is a wasteful number, since it uses less digits than its factorization.

71643021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 823515.

The product of its (nonzero) digits is 1008, while the sum is 24.

The square root of 71643021 is about 8464.2200467615. The cubic root of 71643021 is about 415.3280823638.

Adding to 71643021 its reverse (12034617), we get a palindrome (83677638).

The spelling of 71643021 in words is "seventy-one million, six hundred forty-three thousand, twenty-one".