21234201242 has 4 divisors (see below), whose sum is σ = 31851301866. Its totient is φ = 10617100620.

The previous prime is 21234201221. The next prime is 21234201269. The reversal of 21234201242 is 24210243212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 16525359601 + 4708841641 = 128551^2 + 68621^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5308550309 + ... + 5308550312.

Almost surely, 2^21234201242 is an apocalyptic number.

21234201242 is a deficient number, since it is larger than the sum of its proper divisors (10617100624).

21234201242 is a wasteful number, since it uses less digits than its factorization.

21234201242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10617100623.

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

Adding to 21234201242 its reverse (24210243212), we get a palindrome (45444444454).

The spelling of 21234201242 in words is "twenty-one billion, two hundred thirty-four million, two hundred one thousand, two hundred forty-two".