864132684021 has 20 divisors (see below), whose sum is σ = 1290890088972. Its totient is φ = 576077203008.

The previous prime is 864132684017. The next prime is 864132684029. The reversal of 864132684021 is 120486231468.

It can be written as a sum of positive squares in 2 ways, for example, as 551974702500 + 312157981521 = 742950^2 + 558711^2 .

It is not a de Polignac number, because 864132684021 - 2² = 864132684017 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (864132684029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 7269355 + ... + 7387271.

Almost surely, 2^864132684021 is an apocalyptic number.

864132684021 is a gapful number since it is divisible by the number (81) formed by its first and last digit.

It is an amenable number.

864132684021 is a deficient number, since it is larger than the sum of its proper divisors (426757404951).

864132684021 is a wasteful number, since it uses less digits than its factorization.

864132684021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 208402 (or 208393 counting only the distinct ones).

The product of its (nonzero) digits is 442368, while the sum is 45.

The spelling of 864132684021 in words is "eight hundred sixty-four billion, one hundred thirty-two million, six hundred eighty-four thousand, twenty-one".