68533581 has 4 divisors (see below), whose sum is σ = 91378112. Its totient is φ = 45689052.

The previous prime is 68533571. The next prime is 68533601. The reversal of 68533581 is 18533586.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a de Polignac number, because none of the positive numbers 2^k-68533581 is a prime.

It is a super-2 number, since 2×68533581² = 9393703449367122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68533501) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11422261 + ... + 11422266.

It is an arithmetic number, because the mean of its divisors is an integer number (22844528).

Almost surely, 2^68533581 is an apocalyptic number.

It is an amenable number.

68533581 is a deficient number, since it is larger than the sum of its proper divisors (22844531).

68533581 is a wasteful number, since it uses less digits than its factorization.

68533581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22844530.

The product of its digits is 86400, while the sum is 39.

The square root of 68533581 is about 8278.5011324515. The cubic root of 68533581 is about 409.2303248148.

The spelling of 68533581 in words is "sixty-eight million, five hundred thirty-three thousand, five hundred eighty-one".