68491281 has 4 divisors (see below), whose sum is σ = 91321712. Its totient is φ = 45660852.

The previous prime is 68491273. The next prime is 68491289. The reversal of 68491281 is 18219486.

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 an interprime number because it is at equal distance from previous prime (68491273) and next prime (68491289).

It is not a de Polignac number, because 68491281 - 2³ = 68491273 is a prime.

It is a super-2 number, since 2×68491281² = 9382111146041922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68491289) 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, 11415211 + ... + 11415216.

It is an arithmetic number, because the mean of its divisors is an integer number (22830428).

Almost surely, 2^68491281 is an apocalyptic number.

It is an amenable number.

68491281 is a deficient number, since it is larger than the sum of its proper divisors (22830431).

68491281 is a wasteful number, since it uses less digits than its factorization.

68491281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22830430.

The product of its digits is 27648, while the sum is 39.

The square root of 68491281 is about 8275.9459278079. The cubic root of 68491281 is about 409.1461130306.

The spelling of 68491281 in words is "sixty-eight million, four hundred ninety-one thousand, two hundred eighty-one".