21226563742 has 4 divisors (see below), whose sum is σ = 31839845616. Its totient is φ = 10613281870.

The previous prime is 21226563739. The next prime is 21226563769. The reversal of 21226563742 is 24736562212.

It is a happy number.

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

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 21226563695 and 21226563704.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5306640934 + ... + 5306640937.

It is an arithmetic number, because the mean of its divisors is an integer number (7959961404).

Almost surely, 2^21226563742 is an apocalyptic number.

21226563742 is a deficient number, since it is larger than the sum of its proper divisors (10613281874).

21226563742 is a wasteful number, since it uses less digits than its factorization.

21226563742 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10613281873.

The product of its digits is 241920, while the sum is 40.

The spelling of 21226563742 in words is "twenty-one billion, two hundred twenty-six million, five hundred sixty-three thousand, seven hundred forty-two".