851868249 has 24 divisors (see below), whose sum is σ = 1270095840. Its totient is φ = 506363904.

The previous prime is 851868247. The next prime is 851868253. The reversal of 851868249 is 942868158.

It is not a de Polignac number, because 851868249 - 2¹ = 851868247 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is not an unprimeable number, because it can be changed into a prime (851868247) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9384 + ... + 42329.

It is an arithmetic number, because the mean of its divisors is an integer number (52920660).

Almost surely, 2^851868249 is an apocalyptic number.

It is an amenable number.

851868249 is a deficient number, since it is larger than the sum of its proper divisors (418227591).

851868249 is a wasteful number, since it uses less digits than its factorization.

851868249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51769 (or 51752 counting only the distinct ones).

The product of its digits is 1105920, while the sum is 51.

The square root of 851868249 is about 29186.7820939548. The cubic root of 851868249 is about 947.9617422560.

Subtracting 851868249 from its reverse (942868158), we obtain a palindrome (90999909).

It can be divided in two parts, 8518 and 68249, that added together give a palindrome (76767).

The spelling of 851868249 in words is "eight hundred fifty-one million, eight hundred sixty-eight thousand, two hundred forty-nine".