71840521 has 8 divisors (see below), whose sum is σ = 76200480. Its totient is φ = 67495488.

The previous prime is 71840507. The next prime is 71840557. The reversal of 71840521 is 12504817.

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

It is a cyclic number.

It is not a de Polignac number, because 71840521 - 2¹³ = 71832329 is a prime.

It is a super-2 number, since 2×71840521² = 10322120915102882, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 71840521.

It is not an unprimeable number, because it can be changed into a prime (71840591) 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, 7110 + ... + 13936.

It is an arithmetic number, because the mean of its divisors is an integer number (9525060).

Almost surely, 2^71840521 is an apocalyptic number.

It is an amenable number.

71840521 is a deficient number, since it is larger than the sum of its proper divisors (4359959).

71840521 is a wasteful number, since it uses less digits than its factorization.

71840521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7463.

The product of its (nonzero) digits is 2240, while the sum is 28.

The square root of 71840521 is about 8475.8787744988. The cubic root of 71840521 is about 415.7093804294.

It can be divided in two parts, 71840 and 521, that added together give a square (72361 = 269²).

The spelling of 71840521 in words is "seventy-one million, eight hundred forty thousand, five hundred twenty-one".