20421313040 has 40 divisors (see below), whose sum is σ = 47486340888. Its totient is φ = 8167357440.

The previous prime is 20421313037. The next prime is 20421313043. The reversal of 20421313040 is 4031312402.

It is an interprime number because it is at equal distance from previous prime (20421313037) and next prime (20421313043).

It can be written as a sum of positive squares in 4 ways, for example, as 858255616 + 19563057424 = 29296^2 + 139868^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (20421313043) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 741110 + ... + 768170.

Almost surely, 2^20421313040 is an apocalyptic number.

20421313040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20421313040 is an abundant number, since it is smaller than the sum of its proper divisors (27065027848).

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

20421313040 is a wasteful number, since it uses less digits than its factorization.

20421313040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36507 (or 36501 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 20421313040 its reverse (4031312402), we get a palindrome (24452625442).

The spelling of 20421313040 in words is "twenty billion, four hundred twenty-one million, three hundred thirteen thousand, forty".