8020447581 has 8 divisors (see below), whose sum is σ = 10771988544. Its totient is φ = 5307935840.

The previous prime is 8020447579. The next prime is 8020447583. The reversal of 8020447581 is 1857440208.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (8020447579) and next prime (8020447583).

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 8020447581 - 2¹ = 8020447579 is a prime.

It is a super-2 number, since 2×8020447581² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8020447583) 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, 9756825 + ... + 9757646.

It is an arithmetic number, because the mean of its divisors is an integer number (1346498568).

Almost surely, 2^8020447581 is an apocalyptic number.

It is an amenable number.

8020447581 is a deficient number, since it is larger than the sum of its proper divisors (2751540963).

8020447581 is a wasteful number, since it uses less digits than its factorization.

8020447581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19514611.

The product of its (nonzero) digits is 71680, while the sum is 39.

The square root of 8020447581 is about 89556.9516062265. The cubic root of 8020447581 is about 2001.7025153928.

Adding to 8020447581 its reverse (1857440208), we get a palindrome (9877887789).

The spelling of 8020447581 in words is "eight billion, twenty million, four hundred forty-seven thousand, five hundred eighty-one".