20145505515 has 16 divisors (see below), whose sum is σ = 32449140000. Its totient is φ = 10672159232.

The previous prime is 20145505511. The next prime is 20145505531. The reversal of 20145505515 is 51550554102.

It is a cyclic number.

It is not a de Polignac number, because 20145505515 - 2² = 20145505511 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20145505511) 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, 4504590 + ... + 4509059.

It is an arithmetic number, because the mean of its divisors is an integer number (2028071250).

Almost surely, 2^20145505515 is an apocalyptic number.

20145505515 is a deficient number, since it is larger than the sum of its proper divisors (12303634485).

20145505515 is a wasteful number, since it uses less digits than its factorization.

20145505515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9013806.

The product of its (nonzero) digits is 25000, while the sum is 33.

The spelling of 20145505515 in words is "twenty billion, one hundred forty-five million, five hundred five thousand, five hundred fifteen".