8571220646 has 4 divisors (see below), whose sum is σ = 12856830972. Its totient is φ = 4285610322.

The previous prime is 8571220643. The next prime is 8571220649. The reversal of 8571220646 is 6460221758.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 6460221758 = 2 ⋅3230110879.

It is an interprime number because it is at equal distance from previous prime (8571220643) and next prime (8571220649).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8571220643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2142805160 + ... + 2142805163.

It is an arithmetic number, because the mean of its divisors is an integer number (3214207743).

Almost surely, 2^8571220646 is an apocalyptic number.

8571220646 is a deficient number, since it is larger than the sum of its proper divisors (4285610326).

8571220646 is a wasteful number, since it uses less digits than its factorization.

8571220646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4285610325.

The product of its (nonzero) digits is 161280, while the sum is 41.

The square root of 8571220646 is about 92580.8870447891. The cubic root of 8571220646 is about 2046.5116678494.

The spelling of 8571220646 in words is "eight billion, five hundred seventy-one million, two hundred twenty thousand, six hundred forty-six".