20421431424 has 128 divisors (see below), whose sum is σ = 63817156800. Its totient is φ = 6406705152.

The previous prime is 20421431357. The next prime is 20421431453. The reversal of 20421431424 is 42413412402.

20421431424 is a `hidden beast` number, since 20 + 4 + 214 + 3 + 1 + 424 = 666.

It is a tau number, because it is divible by the number of its divisors (128).

It is a super-2 number, since 2×20421431424² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 115042 + ... + 232545.

Almost surely, 2^20421431424 is an apocalyptic number.

20421431424 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

20421431424 is an abundant number, since it is smaller than the sum of its proper divisors (43395725376).

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

20421431424 is a wasteful number, since it uses less digits than its factorization.

20421431424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 347627 (or 347609 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 27.

Adding to 20421431424 its reverse (42413412402), we get a palindrome (62834843826).

The spelling of 20421431424 in words is "twenty billion, four hundred twenty-one million, four hundred thirty-one thousand, four hundred twenty-four".