20438737565 has 16 divisors (see below), whose sum is σ = 25324755456. Its totient is φ = 15819105600.

The previous prime is 20438737547. The next prime is 20438737651. The reversal of 20438737565 is 56573783402.

It is not a de Polignac number, because 20438737565 - 2¹⁶ = 20438672029 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 603995 + ... + 636935.

It is an arithmetic number, because the mean of its divisors is an integer number (1582797216).

Almost surely, 2^20438737565 is an apocalyptic number.

It is an amenable number.

20438737565 is a deficient number, since it is larger than the sum of its proper divisors (4886017891).

20438737565 is a wasteful number, since it uses less digits than its factorization.

20438737565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36980.

The product of its (nonzero) digits is 4233600, while the sum is 50.

The spelling of 20438737565 in words is "twenty billion, four hundred thirty-eight million, seven hundred thirty-seven thousand, five hundred sixty-five".