21301444240 has 40 divisors (see below), whose sum is σ = 51233651640. Its totient is φ = 8226763776.

The previous prime is 21301444127. The next prime is 21301444291. The reversal of 21301444240 is 4244410312.

21301444240 = T₃₉₈ + T₃₉₉ + ... + T₅₀₃₇.

It can be written as a sum of positive squares in 4 ways, for example, as 23970816 + 21277473424 = 4896^2 + 145868^2 .

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

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, 4588509 + ... + 4593148.

It is an arithmetic number, because the mean of its divisors is an integer number (1280841291).

Almost surely, 2^21301444240 is an apocalyptic number.

21301444240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21301444240 is an abundant number, since it is smaller than the sum of its proper divisors (29932207400).

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

21301444240 is a wasteful number, since it uses less digits than its factorization.

21301444240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9181699 (or 9181693 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 25.

Adding to 21301444240 its reverse (4244410312), we get a palindrome (25545854552).

The spelling of 21301444240 in words is "twenty-one billion, three hundred one million, four hundred forty-four thousand, two hundred forty".