21242120432 has 40 divisors (see below), whose sum is σ = 46929715056. Its totient is φ = 9227344896.

The previous prime is 21242120411. The next prime is 21242120453. The reversal of 21242120432 is 23402124212.

It is an interprime number because it is at equal distance from previous prime (21242120411) and next prime (21242120453).

It is a junction number, because it is equal to n+sod(n) for n = 21242120398 and 21242120407.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3000158 + ... + 3007229.

Almost surely, 2^21242120432 is an apocalyptic number.

It is an amenable number.

21242120432 is an abundant number, since it is smaller than the sum of its proper divisors (25687594624).

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

21242120432 is a wasteful number, since it uses less digits than its factorization.

21242120432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6007425 (or 6007419 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 23.

Adding to 21242120432 its reverse (23402124212), we get a palindrome (44644244644).

The spelling of 21242120432 in words is "twenty-one billion, two hundred forty-two million, one hundred twenty thousand, four hundred thirty-two".