87864643 has 4 divisors (see below), whose sum is σ = 87944008. Its totient is φ = 87785280.

The previous prime is 87864641. The next prime is 87864659. The reversal of 87864643 is 34646878.

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

It is a cyclic number.

It is not a de Polignac number, because 87864643 - 2¹ = 87864641 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 87864593 and 87864602.

It is not an unprimeable number, because it can be changed into a prime (87864641) 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, 37998 + ... + 40243.

It is an arithmetic number, because the mean of its divisors is an integer number (21986002).

Almost surely, 2^87864643 is an apocalyptic number.

87864643 is a deficient number, since it is larger than the sum of its proper divisors (79365).

87864643 is a wasteful number, since it uses less digits than its factorization.

87864643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79364.

The product of its digits is 774144, while the sum is 46.

The square root of 87864643 is about 9373.6141909084. The cubic root of 87864643 is about 444.5678470921.

The spelling of 87864643 in words is "eighty-seven million, eight hundred sixty-four thousand, six hundred forty-three".