21355850436 has 48 divisors (see below), whose sum is σ = 50011976448. Its totient is φ = 7092716800.

The previous prime is 21355850401. The next prime is 21355850437. The reversal of 21355850436 is 63405855312.

It is not an unprimeable number, because it can be changed into a prime (21355850437) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 4079941 + ... + 4085171.

It is an arithmetic number, because the mean of its divisors is an integer number (1041916176).

Almost surely, 2^21355850436 is an apocalyptic number.

It is an amenable number.

21355850436 is an abundant number, since it is smaller than the sum of its proper divisors (28656126012).

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

21355850436 is a wasteful number, since it uses less digits than its factorization.

21355850436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6412 (or 6410 counting only the distinct ones).

The product of its (nonzero) digits is 432000, while the sum is 42.

The spelling of 21355850436 in words is "twenty-one billion, three hundred fifty-five million, eight hundred fifty thousand, four hundred thirty-six".