21355793869 has 16 divisors (see below), whose sum is σ = 22669632000. Its totient is φ = 20061589680.

The previous prime is 21355793863. The next prime is 21355793881. The reversal of 21355793869 is 96839755312.

It is a de Polignac number, because none of the positive numbers 2^k-21355793869 is a prime.

It is a super-2 number, since 2×21355793869² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21355793863) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1212214 + ... + 1229704.

It is an arithmetic number, because the mean of its divisors is an integer number (1416852000).

Almost surely, 2^21355793869 is an apocalyptic number.

It is an amenable number.

21355793869 is a deficient number, since it is larger than the sum of its proper divisors (1313838131).

21355793869 is a wasteful number, since it uses less digits than its factorization.

21355793869 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18048.

The product of its digits is 12247200, while the sum is 58.

The spelling of 21355793869 in words is "twenty-one billion, three hundred fifty-five million, seven hundred ninety-three thousand, eight hundred sixty-nine".