21136435250 has 64 divisors (see below), whose sum is σ = 45635166720. Its totient is φ = 7180228800.

The previous prime is 21136435249. The next prime is 21136435267. The reversal of 21136435250 is 5253463112.

It is a happy number.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 135347 + ... + 246153.

It is an arithmetic number, because the mean of its divisors is an integer number (713049480).

Almost surely, 2^21136435250 is an apocalyptic number.

21136435250 is an abundant number, since it is smaller than the sum of its proper divisors (24498731470).

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

21136435250 is a wasteful number, since it uses less digits than its factorization.

21136435250 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110940 (or 110930 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 32.

Adding to 21136435250 its reverse (5253463112), we get a palindrome (26389898362).

The spelling of 21136435250 in words is "twenty-one billion, one hundred thirty-six million, four hundred thirty-five thousand, two hundred fifty".