85672781 has 4 divisors (see below), whose sum is σ = 85829952. Its totient is φ = 85515612.

The previous prime is 85672777. The next prime is 85672787. The reversal of 85672781 is 18727658.

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 cyclic number.

It is not a de Polignac number, because 85672781 - 2² = 85672777 is a prime.

It is a super-2 number, since 2×85672781² = 14679650808547922, which contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (85672787) 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, 77765 + ... + 78858.

It is an arithmetic number, because the mean of its divisors is an integer number (21457488).

Almost surely, 2^85672781 is an apocalyptic number.

It is an amenable number.

85672781 is a deficient number, since it is larger than the sum of its proper divisors (157171).

85672781 is a wasteful number, since it uses less digits than its factorization.

85672781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157170.

The product of its digits is 188160, while the sum is 44.

The square root of 85672781 is about 9255.9592155541. The cubic root of 85672781 is about 440.8399605765.

It can be divided in two parts, 856 and 72781, that added together give a palindrome (73637).

The spelling of 85672781 in words is "eighty-five million, six hundred seventy-two thousand, seven hundred eighty-one".