8021061864 has 24 divisors (see below), whose sum is σ = 21723709410. Its totient is φ = 2673687264.

The previous prime is 8021061827. The next prime is 8021061967. The reversal of 8021061864 is 4681601208.

It can be written as a sum of positive squares in only one way, i.e., 5566652100 + 2454409764 = 74610^2 + 49542^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is a super-2 number, since 2×8021061864² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 55701747 + ... + 55701890.

Almost surely, 2^8021061864 is an apocalyptic number.

It is an amenable number.

8021061864 is an abundant number, since it is smaller than the sum of its proper divisors (13702647546).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

8021061864 is a wasteful number, since it uses less digits than its factorization.

8021061864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111403649 (or 111403642 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 8021061864 is about 89560.3811068265. The cubic root of 8021061864 is about 2001.7536172971.

The spelling of 8021061864 in words is "eight billion, twenty-one million, sixty-one thousand, eight hundred sixty-four".