71821281 has 8 divisors (see below), whose sum is σ = 109441984. Its totient is φ = 41040720.

The previous prime is 71821241. The next prime is 71821297. The reversal of 71821281 is 18212817.

It is a happy number.

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

It is not a de Polignac number, because 71821281 - 2⁷ = 71821153 is a prime.

It is a super-2 number, since 2×71821281² = 10316592808961922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71821241) 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, 1710010 + ... + 1710051.

It is an arithmetic number, because the mean of its divisors is an integer number (13680248).

Almost surely, 2^71821281 is an apocalyptic number.

It is an amenable number.

71821281 is a deficient number, since it is larger than the sum of its proper divisors (37620703).

71821281 is a wasteful number, since it uses less digits than its factorization.

71821281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3420071.

The product of its digits is 1792, while the sum is 30.

The square root of 71821281 is about 8474.7437129391. The cubic root of 71821281 is about 415.6722659872.

The spelling of 71821281 in words is "seventy-one million, eight hundred twenty-one thousand, two hundred eighty-one".