85721510822 has 4 divisors (see below), whose sum is σ = 128582266236. Its totient is φ = 42860755410.

The previous prime is 85721510779. The next prime is 85721510857. The reversal of 85721510822 is 22801512758.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 22801512758 = 2 ⋅11400756379.

It is a self number, because there is not a number n which added to its sum of digits gives 85721510822.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21430377704 + ... + 21430377707.

It is an arithmetic number, because the mean of its divisors is an integer number (32145566559).

Almost surely, 2^85721510822 is an apocalyptic number.

85721510822 is a deficient number, since it is larger than the sum of its proper divisors (42860755414).

85721510822 is a wasteful number, since it uses less digits than its factorization.

85721510822 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42860755413.

The product of its (nonzero) digits is 89600, while the sum is 41.

The spelling of 85721510822 in words is "eighty-five billion, seven hundred twenty-one million, five hundred ten thousand, eight hundred twenty-two".