20511112240 has 20 divisors (see below), whose sum is σ = 47688336144. Its totient is φ = 8204444864.

The previous prime is 20511112229. The next prime is 20511112283. The reversal of 20511112240 is 4221111502.

It is a tau number, because it is divible by the number of its divisors (20).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 128194372 + ... + 128194531.

Almost surely, 2^20511112240 is an apocalyptic number.

20511112240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20511112240 is an abundant number, since it is smaller than the sum of its proper divisors (27177223904).

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

20511112240 is a wasteful number, since it uses less digits than its factorization.

20511112240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 256388916 (or 256388910 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 19.

Adding to 20511112240 its reverse (4221111502), we get a palindrome (24732223742).

It can be divided in two parts, 2051111 and 2240, that added together give a triangular number (2053351 = T₂₀₂₆).

The spelling of 20511112240 in words is "twenty billion, five hundred eleven million, one hundred twelve thousand, two hundred forty".