85279721 has 4 divisors (see below), whose sum is σ = 86725200. Its totient is φ = 83834244.

The previous prime is 85279673. The next prime is 85279739. The reversal of 85279721 is 12797258.

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, and also an emirpimes, since its reverse is a distinct semiprime: 12797258 = 2 ⋅6398629.

It is a cyclic number.

It is not a de Polignac number, because 85279721 - 2¹⁸ = 85017577 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (85279751) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 722651 + ... + 722768.

It is an arithmetic number, because the mean of its divisors is an integer number (21681300).

Almost surely, 2^85279721 is an apocalyptic number.

It is an amenable number.

85279721 is a deficient number, since it is larger than the sum of its proper divisors (1445479).

85279721 is a wasteful number, since it uses less digits than its factorization.

85279721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1445478.

The product of its digits is 70560, while the sum is 41.

The square root of 85279721 is about 9234.7019984404. The cubic root of 85279721 is about 440.1647471911.

The spelling of 85279721 in words is "eighty-five million, two hundred seventy-nine thousand, seven hundred twenty-one".