71621 has 8 divisors (see below), whose sum is σ = 82944. Its totient is φ = 61120.

The previous prime is 71597. The next prime is 71633. The reversal of 71621 is 12617.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71621 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 71621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71671) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5 + ... + 378.

It is an arithmetic number, because the mean of its divisors is an integer number (10368).

2⁷¹⁶²¹ is an apocalyptic number.

It is an amenable number.

71621 is a deficient number, since it is larger than the sum of its proper divisors (11323).

71621 is a wasteful number, since it uses less digits than its factorization.

71621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 411.

The product of its digits is 84, while the sum is 17.

The square root of 71621 is about 267.6210006707. The cubic root of 71621 is about 41.5285524709.

It can be divided in two parts, 716 and 21, that added together give a palindrome (737).

The spelling of 71621 in words is "seventy-one thousand, six hundred twenty-one".