21969235381 has 8 divisors (see below), whose sum is σ = 23005431360. Its totient is φ = 20939790432.

The previous prime is 21969235361. The next prime is 21969235429. The reversal of 21969235381 is 18353296912.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21969235381 is a prime.

It is a super-2 number, since 2×21969235381² (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 (21969235361) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1681096 + ... + 1694113.

It is an arithmetic number, because the mean of its divisors is an integer number (2875678920).

Almost surely, 2^21969235381 is an apocalyptic number.

It is an amenable number.

21969235381 is a deficient number, since it is larger than the sum of its proper divisors (1036195979).

21969235381 is a wasteful number, since it uses less digits than its factorization.

21969235381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3375515.

The product of its digits is 699840, while the sum is 49.

The spelling of 21969235381 in words is "twenty-one billion, nine hundred sixty-nine million, two hundred thirty-five thousand, three hundred eighty-one".