20145223555 has 16 divisors (see below), whose sum is σ = 25231212864. Its totient is φ = 15411876480.

The previous prime is 20145223513. The next prime is 20145223561. The reversal of 20145223555 is 55532254102.

It is not a de Polignac number, because 20145223555 - 2³³ = 11555288963 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20145223555.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 540997 + ... + 577033.

It is an arithmetic number, because the mean of its divisors is an integer number (1576950804).

Almost surely, 2^20145223555 is an apocalyptic number.

20145223555 is a deficient number, since it is larger than the sum of its proper divisors (5085989309).

20145223555 is a wasteful number, since it uses less digits than its factorization.

20145223555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40926.

The product of its (nonzero) digits is 60000, while the sum is 34.

Adding to 20145223555 its reverse (55532254102), we get a palindrome (75677477657).

The spelling of 20145223555 in words is "twenty billion, one hundred forty-five million, two hundred twenty-three thousand, five hundred fifty-five".