21432300440 has 32 divisors (see below), whose sum is σ = 48281060880. Its totient is φ = 8562540672.

The previous prime is 21432300437. The next prime is 21432300451. The reversal of 21432300440 is 4400323412.

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, 290867 + ... + 357026.

Almost surely, 2^21432300440 is an apocalyptic number.

21432300440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21432300440 is an abundant number, since it is smaller than the sum of its proper divisors (26848760440).

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

21432300440 is a wasteful number, since it uses less digits than its factorization.

21432300440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 648731 (or 648727 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 23.

Adding to 21432300440 its reverse (4400323412), we get a palindrome (25832623852).

The spelling of 21432300440 in words is "twenty-one billion, four hundred thirty-two million, three hundred thousand, four hundred forty".