20218344587 has 4 divisors (see below), whose sum is σ = 23106679536. Its totient is φ = 17330009640.

The previous prime is 20218344583. The next prime is 20218344593. The reversal of 20218344587 is 78544381202.

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 20218344587 - 2² = 20218344583 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20218344583) 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, 1444167464 + ... + 1444167477.

It is an arithmetic number, because the mean of its divisors is an integer number (5776669884).

Almost surely, 2^20218344587 is an apocalyptic number.

20218344587 is a deficient number, since it is larger than the sum of its proper divisors (2888334949).

20218344587 is an equidigital number, since it uses as much as digits as its factorization.

20218344587 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2888334948.

The product of its (nonzero) digits is 430080, while the sum is 44.

The spelling of 20218344587 in words is "twenty billion, two hundred eighteen million, three hundred forty-four thousand, five hundred eighty-seven".