21401424144 has 60 divisors (see below), whose sum is σ = 60204674556. Its totient is φ = 7096836096.

The previous prime is 21401424127. The next prime is 21401424223. The reversal of 21401424144 is 44142410412.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 6121497600 + 15279926544 = 78240^2 + 123612^2 .

It is a super-2 number, since 2×21401424144² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 357237 + ... + 412820.

Almost surely, 2^21401424144 is an apocalyptic number.

21401424144 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21401424144 is an abundant number, since it is smaller than the sum of its proper divisors (38803250412).

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

21401424144 is a wasteful number, since it uses less digits than its factorization.

21401424144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 770264 (or 770255 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 27.

Adding to 21401424144 its reverse (44142410412), we get a palindrome (65543834556).

The spelling of 21401424144 in words is "twenty-one billion, four hundred one million, four hundred twenty-four thousand, one hundred forty-four".