21135136146 has 16 divisors (see below), whose sum is σ = 42272354784. Its totient is φ = 7044698304.

The previous prime is 21135136129. The next prime is 21135136181. The reversal of 21135136146 is 64163153112.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 65805 + ... + 215871.

It is an arithmetic number, because the mean of its divisors is an integer number (2642022174).

Almost surely, 2^21135136146 is an apocalyptic number.

21135136146 is an abundant number, since it is smaller than the sum of its proper divisors (21137218638).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21135136146 is a wasteful number, since it uses less digits than its factorization.

21135136146 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173545.

The product of its digits is 12960, while the sum is 33.

Adding to 21135136146 its reverse (64163153112), we get a palindrome (85298289258).

The spelling of 21135136146 in words is "twenty-one billion, one hundred thirty-five million, one hundred thirty-six thousand, one hundred forty-six".