21212143432 has 32 divisors (see below), whose sum is σ = 40893350400. Its totient is φ = 10309161600.

The previous prime is 21212143399. The next prime is 21212143481. The reversal of 21212143432 is 23434121212.

It is an alternating number because its digits alternate between even and odd.

It is a junction number, because it is equal to n+sod(n) for n = 21212143397 and 21212143406.

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, 30432 + ... + 208207.

It is an arithmetic number, because the mean of its divisors is an integer number (1277917200).

Almost surely, 2^21212143432 is an apocalyptic number.

It is an amenable number.

21212143432 is a deficient number, since it is larger than the sum of its proper divisors (19681206968).

21212143432 is a wasteful number, since it uses less digits than its factorization.

21212143432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 238957 (or 238953 counting only the distinct ones).

The product of its digits is 2304, while the sum is 25.

Adding to 21212143432 its reverse (23434121212), we get a palindrome (44646264644).

The spelling of 21212143432 in words is "twenty-one billion, two hundred twelve million, one hundred forty-three thousand, four hundred thirty-two".