21221031242 has 32 divisors (see below), whose sum is σ = 33115899600. Its totient is φ = 10186702848.

The previous prime is 21221031233. The next prime is 21221031263. The reversal of 21221031242 is 24213012212.

It can be written as a sum of positive squares in 8 ways, for example, as 12465499201 + 8755532041 = 111649^2 + 93571^2 .

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, 12713984 + ... + 12715652.

Almost surely, 2^21221031242 is an apocalyptic number.

21221031242 is a deficient number, since it is larger than the sum of its proper divisors (11894868358).

21221031242 is a wasteful number, since it uses less digits than its factorization.

21221031242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2810.

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 21221031242 its reverse (24213012212), we get a palindrome (45434043454).

The spelling of 21221031242 in words is "twenty-one billion, two hundred twenty-one million, thirty-one thousand, two hundred forty-two".