85722857221 has 4 divisors (see below), whose sum is σ = 90765378252. Its totient is φ = 80680336192.

The previous prime is 85722857189. The next prime is 85722857237. The reversal of 85722857221 is 12275822758.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 72166912321 + 13555944900 = 268639^2 + 116430^2 .

It is a cyclic number.

It is not a de Polignac number, because 85722857221 - 2⁵ = 85722857189 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 (85722857281) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2521260490 + ... + 2521260523.

It is an arithmetic number, because the mean of its divisors is an integer number (22691344563).

Almost surely, 2^85722857221 is an apocalyptic number.

It is an amenable number.

85722857221 is a deficient number, since it is larger than the sum of its proper divisors (5042521031).

85722857221 is a wasteful number, since it uses less digits than its factorization.

85722857221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5042521030.

The product of its digits is 1254400, while the sum is 49.

The spelling of 85722857221 in words is "eighty-five billion, seven hundred twenty-two million, eight hundred fifty-seven thousand, two hundred twenty-one".