21252227742 has 20 divisors (see below), whose sum is σ = 47620732896. Its totient is φ = 7084075860.

The previous prime is 21252227741. The next prime is 21252227747. The reversal of 21252227742 is 24772225212.

21252227742 is a `hidden beast` number, since 21 + 2 + 522 + 2 + 77 + 42 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 21252227697 and 21252227706.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21252227741) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 65593134 + ... + 65593457.

Almost surely, 2^21252227742 is an apocalyptic number.

21252227742 is an abundant number, since it is smaller than the sum of its proper divisors (26368505154).

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

21252227742 is a wasteful number, since it uses less digits than its factorization.

21252227742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131186605 (or 131186596 counting only the distinct ones).

The product of its digits is 62720, while the sum is 36.

The spelling of 21252227742 in words is "twenty-one billion, two hundred fifty-two million, two hundred twenty-seven thousand, seven hundred forty-two".