85121861 has 4 divisors (see below), whose sum is σ = 92860224. Its totient is φ = 77383500.

The previous prime is 85121849. The next prime is 85121879. The reversal of 85121861 is 16812158.

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 85121861 - 2⁶ = 85121797 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (85121801) 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, 3869165 + ... + 3869186.

It is an arithmetic number, because the mean of its divisors is an integer number (23215056).

Almost surely, 2^85121861 is an apocalyptic number.

It is an amenable number.

85121861 is a deficient number, since it is larger than the sum of its proper divisors (7738363).

85121861 is a wasteful number, since it uses less digits than its factorization.

85121861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7738362.

The product of its digits is 3840, while the sum is 32.

The square root of 85121861 is about 9226.1509309137. The cubic root of 85121861 is about 439.8929853382.

The spelling of 85121861 in words is "eighty-five million, one hundred twenty-one thousand, eight hundred sixty-one".