20397785587 has 16 divisors (see below), whose sum is σ = 21117451680. Its totient is φ = 19691223552.

The previous prime is 20397785579. The next prime is 20397785609. The reversal of 20397785587 is 78558779302.

It is a cyclic number.

It is not a de Polignac number, because 20397785587 - 2³ = 20397785579 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20397785567) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3580113 + ... + 3585805.

It is an arithmetic number, because the mean of its divisors is an integer number (1319840730).

Almost surely, 2^20397785587 is an apocalyptic number.

20397785587 is a deficient number, since it is larger than the sum of its proper divisors (719666093).

20397785587 is a wasteful number, since it uses less digits than its factorization.

20397785587 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6822.

The product of its (nonzero) digits is 29635200, while the sum is 61.

The spelling of 20397785587 in words is "twenty billion, three hundred ninety-seven million, seven hundred eighty-five thousand, five hundred eighty-seven".