21430213444 has 24 divisors (see below), whose sum is σ = 38081260448. Its totient is φ = 10550010240.

The previous prime is 21430213421. The next prime is 21430213457. The reversal of 21430213444 is 44431203412.

It is a super-2 number, since 2×21430213444² (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 7 ways as a sum of consecutive naturals, for example, 560647 + ... + 597649.

Almost surely, 2^21430213444 is an apocalyptic number.

It is an amenable number.

21430213444 is a deficient number, since it is larger than the sum of its proper divisors (16651047004).

21430213444 is a wasteful number, since it uses less digits than its factorization.

21430213444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39235 (or 39233 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 28.

Adding to 21430213444 its reverse (44431203412), we get a palindrome (65861416856).

The spelling of 21430213444 in words is "twenty-one billion, four hundred thirty million, two hundred thirteen thousand, four hundred forty-four".