851722 has 4 divisors (see below), whose sum is σ = 1277586. Its totient is φ = 425860.

The previous prime is 851689. The next prime is 851723. The reversal of 851722 is 227158.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 848241 + 3481 = 921^2 + 59^2 .

It is not an unprimeable number, because it can be changed into a prime (851723) by changing a digit.

851722 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 212929 + ... + 212932.

2⁸⁵¹⁷²² is an apocalyptic number.

851722 is a deficient number, since it is larger than the sum of its proper divisors (425864).

851722 is a wasteful number, since it uses less digits than its factorization.

851722 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 425863.

The product of its digits is 1120, while the sum is 25.

The square root of 851722 is about 922.8878588431. The cubic root of 851722 is about 94.7907490365.

The spelling of 851722 in words is "eight hundred fifty-one thousand, seven hundred twenty-two".