20533144440 has 32 divisors (see below), whose sum is σ = 61599433680. Its totient is φ = 5475505152.

The previous prime is 20533144433. The next prime is 20533144483. The reversal of 20533144440 is 4444133502.

It is a super-2 number, since 2×20533144440² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 20533144398 and 20533144407.

It is a congruent 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, 85554649 + ... + 85554888.

Almost surely, 2^20533144440 is an apocalyptic number.

20533144440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20533144440 is an abundant number, since it is smaller than the sum of its proper divisors (41066289240).

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

20533144440 is a wasteful number, since it uses less digits than its factorization.

20533144440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171109551 (or 171109547 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 30.

Adding to 20533144440 its reverse (4444133502), we get a palindrome (24977277942).

The spelling of 20533144440 in words is "twenty billion, five hundred thirty-three million, one hundred forty-four thousand, four hundred forty".