21212404232240 has 80 divisors (see below), whose sum is σ = 55421840150208. Its totient is φ = 7491738743808.

The previous prime is 21212404232237. The next prime is 21212404232269. The reversal of 21212404232240 is 4223240421212.

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 443379179 + ... + 443427018.

Almost surely, 2^{21212404232240} is an apocalyptic number.

21212404232240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21212404232240 is an abundant number, since it is smaller than the sum of its proper divisors (34209435917968).

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

21212404232240 is a wasteful number, since it uses less digits than its factorization.

21212404232240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 886806246 (or 886806240 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 29.

Adding to 21212404232240 its reverse (4223240421212), we get a palindrome (25435644653452).

The spelling of 21212404232240 in words is "twenty-one trillion, two hundred twelve billion, four hundred four million, two hundred thirty-two thousand, two hundred forty".