21221212043242 has 8 divisors (see below), whose sum is σ = 31841881880256. Its totient is φ = 10607251416492.

The previous prime is 21221212043237. The next prime is 21221212043287. The reversal of 21221212043242 is 24234021212212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21221212043242.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1677294658 + ... + 1677307309.

It is an arithmetic number, because the mean of its divisors is an integer number (3980235235032).

Almost surely, 2^{21221212043242} is an apocalyptic number.

21221212043242 is a deficient number, since it is larger than the sum of its proper divisors (10620669837014).

21221212043242 is a wasteful number, since it uses less digits than its factorization.

21221212043242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3354605132.

The product of its (nonzero) digits is 6144, while the sum is 28.

Adding to 21221212043242 its reverse (24234021212212), we get a palindrome (45455233255454).

The spelling of 21221212043242 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred twelve million, forty-three thousand, two hundred forty-two".